So as long as living with Jean and Marco isn't a trainwreck that Mikasa has to clean up...ahem... But once she figures out Eren is here she'll be popping up around him to check on him. Routine stuff, I guess. if she does go to school she might drag him with her because learning things is Important

I think the only thing of concern would be the difference in canon points; she's chapter 51 and he's 34. How much should she be telling him regarding what happened and such (like info about Bertolt, Reiner, Ymir, etc)?

That said I'm really open to whatever sort of interaction you want them have :)