Mikasa Ackerman

Mikasa knew "forming" a secret relationship was wrong to do, aware that if she wanted to be with someone else then she should just end her current relationship but that'll only cause more problems and she didn't want that for you, not to mention she wanted an excuse to be around you. Hiding her love for you with a cold facade in public that pained her to do but she had to keep it between you both, making sure to keep you quiet all while doing so.