A/N: This is an ending that has a major plot hole, called Misa and Rem, for context, just pretend that this relationship works somehow.
Two Months Later
Light is currently typing really fast on his computer, with (Y/n) on his lap, L next to them who is facing the wrong way on the chair. "Ryuzaki, I know you aren't feeling up to it, but come over here for a second" Light said to L, so L started to roll his chair over to Light and (Y/n).
"Take a close look at this, you too (Y/n)" Light said, clicking on a link that shows a table graph. "Take a look at this, it can't be coincidence," Light said, it is a graph of CEOs and businessmen who all died of heart attacks. "It looks to me, Kira is supporting Yotsuba..." (Y/n) said, basically saying Light's opinion as well.
"Hmm... It could be... But what you're saying is true, we can assume that punishing criminals is not this Kira's real intent" L said, using his deducting skills to figure that out. "Right, punishing criminals is a diversion for him, it obscures the fact that he's actually killing people for the benefit of his company," Light said, then he suddenly smirked.
"Are you... Feeling a bit more motivated now?" Light asks L, 'looks like Light and L are finally becoming real friends!' (Y/n) cheered in her mind, maybe slightly shipping them. Even though they obviously only like her as a lover and not each other, that won't stop her from shipping them.
Both L and Light have been working well together, and even cooperating with each other to find evidence about the new Kira. Last night, unknown to (Y/n), they came to an agreement, "we both know we are in love with (Y/n), I say we share her" Light suggested to L.
"I don't know... I don't really like you that much" L said, quite uncertain about this idea. "Come on, we work well together, and we can protect her together, and you can replace Misa's place," Light said, trying to convince the male. "Do we have to love each other?" L asked Light, wanting to know if he has to love another male.
"No, just (Y/n), and we tolerate each other" Light said with a disgusted look, "very well, I accept, but we don't get rid of Misa till after the case is solved," L said, "so it's agreed?" Light asked, which earned a nod from L. Throughout the whole investigation, they decided to always pull (Y/n) in between the two of them, and away from Misa.
Eventually, they caught the new Kira, and instead of giving Light the notebook, L kept it to lock it away from sight. "Why can't I see the book?" Light asked L, quite annoyed that he can't see the tool that kills people. "So that you don't gain Kira's powers, I'm locking it away, then getting my memories erased of it," L said.
"Light... L... Please don't fight, we caught Kira, we should be celebrating" (Y/n) said, making the two males look at her. "Sorry, (Y/n), very well, lock it away," Light said to L. L did just that, he locked it away in a secluded prison that the FBI guards, L forgot everything about the book, but knows he caught Kira.
"Thank you for the food!" Everyone in the task force said with a smile, "I can't believe we finally caught Kira! The case is officially closed!" Matsuda said with a smile. "We can finally go back to our normal lives" (Y/n) said while being hand-fed by Light and L, much to Misa's annoyance.
"Hey! Why are you keeping her all to yourselves?! I'm her girlfriend! I should get time with her too!" Misa announced, finally fed up with the males making (Y/n) avoid her. "We've decided that we don't want you to be her girlfriend, now that the case is closed, you're useless" L said quite rudely.
"What...? That's mean! You can't just decide that I'm no longer her girlfriend!" Misa yelled with a sad look. "We can, and we will, I never liked you Misa, and I made it very obvious from the start," Light said, a little less rudely. "Guys... That's not very- Mpfh?!" (Y/n) tried saying, but L shoved some food in her mouth.
In the end, they chased Misa away, and (Y/n) gave them the silent treatment for being mean to Misa. "(Y/n), we said we're sorry, we just love you too much" Light said, gently grabbing her from her waist. (Y/n) huffed and crossed her arms, turning her face away from Light, she goes to move out of his hold, but L blocks her way.
Now she is sandwiched between the two males, while in her room, "l-let go of me- Mpfh?!" Once again she was silenced, but this time was because Light kissed her, once he stopped kissing her, L decided to kiss her as well. After their... Fun, (Y/n) decided to forgive them, sort of.
Now, she has two husbands, Light became a police chief, and L is still the police's special investigator. To keep (Y/n) out of harm's way, they decided to make her a housewife, not that (Y/n) is complaining. Who would say no to a bunch of free time? Then greeted by two lovely husbands who come home from a long day of work.