Living Forever Is Hard (Demon!Levi)

Humanity's strongest babysitter

I'm scared. This morning Erwin and a small group of the vets including my squad left to go on a small expedition but it was raining so I couldn't go. The rain has now escalated into thunder. Erwin hasn't got back either, or at least not that I know of because I'm hiding under our bed. Yes, I hide from the thunder. I can't help it, I just feel safer. It's cold under here too, I wish Erwin was here. I hope he's okay.

"Levi. Leeevvii." Someone's voice was disrupting my sleep. I wanted to tell them to go away, for some reason I felt really tired. But regardless, I slowly decided to open my eyes. "That's it, wakey wakey. We're back." I recognize that voice.
"Petra?" I ask as my eyes finally open.
"Yep, the Commander said you'd be under here, so he told me to check if you were okay while he dealt with some Military Police who were here when we got back." I like Petras voice it's so soft and comforting. "Why don't you come out, the rain has stopped." Oh shit, I'm still under my bed, fuck. In my haste to get out I bang my head, causing me to make a high pitched yelp. Petra was laughing when I finished crawling out. "What?" I hiss as I tuck my tail back under my shirt, keeping a sour pout on my lips.
"Sorry Captain but that was rather cute." She continued to giggle for a moment before she cleared her throat and straightened up. I shake my head and pick up my jacket, I don't have any of my belts on at the moment but I put it on anyway.
"Is Erwin in his office?"
"Probably, he might even be finished by now." Petra replied obediently.
"Thank you, do you have anything else you want to say to me or are we done." I try not to snap at her, it's been a long day and I need Erwin cuddles.
"Well other than the fact you can't denie that you're soft in the middle, no. You can go hug your boyfriend now."
"Don't call him that, it sounds weird." I snap but I can feel how red my cheeks are so she just laughs at me, waving over her shoulder as she walks away.

I burst in the door not caring if someone's inside. Luckily no one is, I make a beeline for Erwins arms. Gah, I love his hugs, so warm and squishy. "Were you hiding again?" His soft voice is like candy to me.
"No, I was... keeping the floor under our bed company. It gets really lonely down there." Nice one Levi, now you sound like a four year old.
"Cute."
"What is with people calling me that, first Petra, now you. I'm not cute."
"Now of course not. Hey, babe the Military Police are asking a favour of you."

Okay, so I'm super confused. Erwin spends our cuddle time talking about a new recruit down in the Military Police's jail with a strange ability. Apparently he can turn into a titan and control it. This is a kid we're talking about, a fifthteen year old kid. One, is that even possible and two, a kid, really; don't you think that's a bit of a tall order for a kid to be able to deal with. But apparently he helped block the wall with his power bluh bluhbluh. And no I'm not jealous! I'm just struggling to believe this bull. But whatever Erwin believes it so I have to trust him.

Erwin and I are going to see this, kid. The military police have him a the moment so we have to go to them. One of them is leading us to the cell and talk about... something. We finally get there and the little fucker's asleep. No, I haul my ass all the way to his cell and he isn't even awake. Erwin gives me that look that says 'Play nice, Levi.' Fine, okay I can maybe give him a chance. The guards both disappear, leaving us alone. "I know you don't want to do this, Levi. But please, he could be useful." Erwin whispers. Oh yeah that's another thing he wants me to look after the kid, cause I'm the only one strong enough to kill him if he fucks about.
"Oh yeah don't worry, I'll just become Humanity's strongest babysitter." I lean back against the wall and cross my arms. Erwin sighs, "I'll give you a treat if we win this court case." I let out a curt laugh, "You're gonna have to be begging on your knees for at least a week before I'll let you 'treat me'." I make quotation mark with my fingers.
"You can do whatever you want to me for a month." The kid start to stir as Erwin spoke. I smirk to myself, "Done deal."

'I'm gonna kill them all' Ahha good luck with that kid. Damn that boy has some freaky determination. Kinda like Erwin but not, Erwins bigger and stronger and cooler and down right gorgeous. But yeah I could kill the kid if I had too, I mean I was just kicking him in the face. And let me tell you that was the most fun I've had in years. And that meant that we won the trail. Now I get to control Erwin for a whole month! But on the down side I need to look after the brat for a while, bring him into my squad. Ew, just the thought of it makes me ill. At least Hanji will pester him with her strange experiments instead of me.
Okay back to Erwin, what am I gonna do to him?

Erwin is apparently an amazing begger. Like damn, I was struggling to stay controlled tonight. Ah, just thinking about it now makes me hot again; him literally on his knees in front of me, kissing everywhere he could, begging and his hips bucking at nothing. Holy crap he knows how to drive a man crazy, even when he's supposed to be the one going crazy. Now I lay in his arms all fuzzy and fucked out. I am so glad I chose him as my life mate, well done brain or maybe penis, I don't know which one decided but whichever one it is you did good.

(This one was a little shorter because I needed to moved to story along without taking a huge time jump. But whatever I hope you stick around for more.)