Requested by @kiowrites_
It was no secret that Mammon had a crush on you. Since the moment you locked eyes he was enamored with you. He tried multiple times to confess to you, but would always mess it up somehow.
"Y/n! I uhh...I got you this rose." Mammon
"Huh? Sorry I didn't hear you..."
"I-I said YOU'RE GROSS-"
Despite all the errors he made, he was grateful you were patient with him. Finally, he managed to push through his nerves and ask you out. You've been dating for a few months now.
Mammon tried his hardest to be the best boyfriend he could be. He would take you out, spoil you, and tried his best to be affectionate. Affection was always a challenge for the shy demon, but for you, he would do anything.
All but one thing...
He never did simply say 'I love you'. He would get too flustered or shut down whenever he tried it. On top of that, he never knew the right time to say it. It did bum you out a bit, but you decided not to say anything about it.
Mammon didn't seem to notice how much it was upsetting you until it smacked him in the face.
"You don't have to go, do ya? I mean...ya could always pretend yer sick or somethin' and stay with the great Mammon!" Mammon wrapped his arms around your waist.
"Mams, I told you I can't get out of this meeting, it's important." You said as you placed your hands on his chest.
"Then let me go with you!" Mammon pouted.
"You and I both know Lucifer would tie you up before you step foot into the meeting room." You snickered. Mammon just made a face.
"Oh come on...What do you normally do when I'm gone?" You asked.
"...w-wait for ya to come back." Mammon mumbled as his cheek grew pink.
You couldn't help but laugh at how adorable Mammon was being.
"I'll be back soon, don't worry hun." You chuckled.
"Hmph...fine. But hurry up, okay?! I already miss ya..." Mammon huffed.
"Alright, alright...I'll see you soon." You said before kissing him. He lingered just a bit longer, he really didn't want to let you go.
"S-see ya..." He blushed. He sighed a bit as he watched you leave.
"That's it?! No 'I love you' or anything??? Really?!" Asmo suddenly appeared.
"DAH! WHAT THE F- HOW LONG WERE YA THERE?!" Mammon felt his soul almost left his body.
"We've been here for a while now! You were just too busy making goo-goo eyes at Y/n to notice!" Asmo said.
"We?!" Mammon freaked as he looked frantically around the living room.
"I'm here too, you moron." Satan said as he got off the couch. Mammon turned away in embarrassment.
"Anyways...I've never heard you tell Y/n that you love them...how come?" Satan asked. He didn't really mean it as a tease, just more out of his own curiosity.
"Yeah! What are you waiting for?" Asmo put his hands on his hips.
"N-nothing?! I dunno!" Mammon stomped. He didn't want to get into it, thinking that his brothers would just make fun of him.
"Well, you should say it soon before Y/n starts getting more sad about it." Satan said.
"I'm not- wait did you say more..?" Mammon said.
"You mean you haven't noticed?" Satan looked perplexed.
"Argh...no I didn't." Mammon groaned. Satan and Asmo just shook their head in disappointment.
"Well...if you don't tell Y/n sooner or later...I might just snatch them up for myself~" Asmo smirked.
"Hah?! Like hell I'd let you do that!" Mammon barked.
Before things could escalate, you came back into the living room, surprising the three demons.
"Sorry...I just realized I forgot something." You said as you quickly rummaged through some things.
"Ah! Here it is...okay I'm going for real now." You chuckled.
"Bye, Y/n!! Stay safe! Love you~" Asmo smiled at you.
"Umm...l-love you too??" You stood there confused for a moment. Mammon glared at Asmo.
"U-Uh Y/n, wait!" Mammon said.
"Hm? What's wrong, hun?" You asked.
"I-I uhh...w-well y-you see I erm...I l-love...y...your hair! Ya look gr-great, sweetheart." Mammon stuttered.
"Are you guys trying to prank me or something..?" Your brows knitted in confusion.
"Nope, I'm sorry about these two...you can go to the meeting now." Satan intervened.
"Alright...see you guys later." You looked at them funny before leaving.
"Wow...smooth operator-" Asmo teased.
"Shut up!"
After that whole ordeal, Mammon locked himself in his room and thought of how to tell you how much he loved you. He started feeling bad that he didn't say it sooner, but there wasn't much he could about it now. He paced back and forth, racking his brain over how to impress you.
"Maybe candles...? Hmm...w-woah!" He suddenly tripped over something, landing face-first on the floor.
"Oww...what the heck..?" He rubbed his head and tried looking for what he tripped on.
Mammon realized he tripped over a firework he...'bought' and ultimately forgot about in a rush to hide it from Lucifer. That's when it hit him.
He scrambled to his feet and hid the firework again, this time where he wouldn't trip over it. He ran out of his room, eagerly looking for Satan.
"Asmo I don't think glitter is going to fix eyebags-"
"Satan! I need a favor!" Mammon came storming in.
"Whatever for?" Satan raised a brow.
"You know that one guy who made the fireworks during the summer festival, right?" Mammon asked.
"Of course...are you saying you want fireworks..? You know Lucifer would kill you if he caught wind of this." Satan said.
"Well, I don't want them for me! I-I'm plannin' on doing something for Y/n on our anniversary..." Mammon's cheeks grew pink.
"Aww! You're planning on telling Y/n you love them aren't you?!" Asmo gasped.
"Would ya quiet down?! I don't want anyone else to know, okay?!" Mammon's face was beet red.
"Hm...I might be able to pull some strings, but it's going to cost you quite a bit." Satan said.
"That doesn't matter! How much would it cost?!" Mammon asked.
"Well...depending on how extravagant you want the show to be it's going to cost 10,000 to 50,000 grimm. That is if you get on his good side." Satan said.
"...okay maybe it does matter." Mammon deflated.
"Aw cheer up, Mammon! Maybe we could help get you some quick cash! I know some fashion lines that would love to have you model for them~" Asmo smirked.
"W-what kind of fashion lines...?" Mammon asked, not liking the way Asmo said it.
"Oh, you'll see~"
After some modeling gigs, part-time jobs, and totally not stealing any money from his brothers, Mammon finally scrounged enough money to surprise you the day of your anniversary.
He woke up with a start and excitedly rushed to your room. He already planned the entire day and couldn't wait to spend time with you.
"Mornin' sunshine!" Mammon said as he burst into the room.
"Mammon it's too early for your shenanigans..." You mumbled before burying your head in your pillow.
"Aw c'mon, sweetheart! Don't tell me you forgot what day it is!" Mammon whined.
"Saturday..?" You sleepily said.
"Besides that!" Mammon huffed.
"I'm kidding...happy anniversary, hun." You gave him a tired smile.
"I have the whole day planned out for us, let's go!!" Mammon jumped.
"Mnm...give me five more minutes..." You yawned.
"Y/nnnn!" He whined.
"Alright alright...I'm up." You chuckled.
"I'll be waitin' by the entrance!" Mammon chirped. He ran out before you could stop him.
You tiredly got ready and went to go meet Mammon with a gift in hand.
"Y/n! Took ya long...what's that?" Mammon asked.
"A gift I got you. There's some more in my room but we can worry about those later. I want you to open this first." You said as you handed him a small box.
He carefully opened it and found matching jewelry for the two of you.
"You always go on about having matching stuff, so...I hope you like them." You smiled.
"Th-they're nice..." Mammon teared up.
"Hey don't cry about it!"
After calming Mammon down and putting on the jewelry, you finally went out to see whatever Mammon was planning.
He took you out to eat first, taking you to your favorite restaurant. Following right after, he brought you to an amusement park that you've been dying to go to for a while. You two spent almost the entire day there, trying to go on every single ride. It was late at night when Mammon told you he wanted to show you something important.
"Where are you taking me?" You laughed.
"Just wait! It's gonna be cool, I promise!" Mammon said.
He finally brought you to a place where you could see the entirety of Devildom. The colorful lights illuminating the place were quite breathtaking.
"Woah...it's pretty." You looked around in awe.
"It's gonna get prettier in a moment!" Mammon said as he took your hand.
"What do you m-"
The sky suddenly lit up with colorful fireworks. Thousands of them went off almost simultaneously. It took you a second to realize it spelled out something.
'I LOVE YOU, Y/N' was painted across the starry night for all of Devildom to see.
You turned to Mammon in shock and found him standing there with the biggest smile on his face.
"Y-Y/n, I love you... and I'm so in love with ya that I'm willin' to let everyone in Devildom know." Mammon said.
"...took you long enough." You hugged him tightly.
"A-At least I said it!" He blushed.
"Are you implying that I should say it too?" You teased.
"I-I mean...not if y-you want...t-mn!" Mammon stuttered before you kissed his lips passionately.
Mammon froze for a moment before melting into the kiss, placing his hands on your waist so he could hold you better. Nothing had to be said to show how much you truly loved each other. Mammon felt himself falling deeper for you with every kiss you shared. You two broke away panting a bit but still smiling.
"I love you too, great Mammon."