A Demon's Blood Oath (Grandson of Inuyasha M!Reader x Demon Slayer)

You Become A Tsuguko

You were holding Zenitsu, Tanjiro, and Inosuke. Inosuke and Tanjiro on your shoulders and dragging Zenitsu... well until Nezuko 'Mmm'ed at you to carry him properly, to which you then were basically forced too. When you got to the estate, the agents took them inside and went in. Miki came rushing out to you, and luckily it was night time when you all arrived. "Y/n! Are you okay?! I heard what happened!"

"I'm fine, I'm fine." You numbered and took off the top of your robe. Nezuko blushed and looked away. You pointed to the scar on your chest. "Still got this scar, but it's the only one."

"From what I heard, you're supposed to be a torso and a head." Miki crossed her arms and you scratched your head.

"Yeah, Grandpa saved me..." You then half squinted your eyes with a bit of annoyance. "He did put his hand in my heart but that's besides the point."

"You must have scared Nezuko." Miki said as you looked at Nezuko, who was still holding your hand. She clenched on to it and nodded. She didn't know if you knew this, but you weren't seen as Nezuko's family. You remained that same in her mind. Not that she could tell you that, but if you knew(which you did), you'd probably blush and not say anything anyway, which you did. Miki slapped you on the back. "That's something you gotta work on!"

"I've been meaning to ask you, aren't you part demon too?" the question was asked and she scratched her face.

"Well, yeah but... I didn't go through your training so, I doubt I'd be any help in the field. I mean, I experimented a bit with mom's now but nothing much." Miki stated as you crossed... actually no, you didn't. Nezuko finally let go of your arm but you looked at her in confusion. She shrank so much that you didn't even hesitate to put her on your shoulders. You then gained a serious face as Nezuko ran her fingers through your hair.

"Sis, where is Shinobu?" You asked her as she was trying to take you seriously... as much as she could.

"Uh...In the medical bay..."

You then walked to the medical bay and saw Shinobu leaving. "SHINOBU!!"

"Hmm? Oh, Y/n." Shinobu said her usual smile and looked you up and down. "I'm glad your in a stable condition."

"How are they looking?" You asked and she sighed.

"Inosuke's poison... there's nothing I can do but try and extract it. But he shifted his organs around so that makes it even more complicated." Shinobu explained as she closed the door to the beds. "Tanjiro is in a coma, but stable. Zenitsu is already healed, but sleeping."

"Good... that's good. I have a favor to ask..." you got down on your knees and Shinobu was shocked. You put your head to the ground. "I know this is a lot to ask of me. But can you take me under your wing?"

"To say I'm shocked is to say the least. I most certainly wasn't expecting your favor to be so dire that you had to get on your knees." Shinobu teased but held genuine confusion. "What makes you want to be under me?"

Your mind went back to the fight. "After the fight with Daki and her brother, I learned that I'm so dependent on my form, and I've gotten sloppy with my skills. Urokodaki would've slapped the shit out of me if I blew it. But, I also learned how dangerous posion was."

Images of Inosuke being stabbed, Uzui's small cut, your body being sliced off. "I need to kill my enemies slowly without them realizing it, but the only way I could learn that skill set is through Insect Breathing, right? This is the only way I can feel certain that I can kill a demon for good."

"Although your courage is well spent, I have to advise against it." She gained a more serious tone but kept her smile. "Insect Breathing is a Breathing Style for me specifically because I can't cut through a demon's neck because of my lack of physical strength... but you can."