She seems so nervous (Probably never had someone take much interest in her feet or even her.) and slightly embarrassed (What if they're not tidy or they smell.) yet flattered that you are at her feet. ("You're doing this for me?! I-I don't know what to do... I am kind of tired and my feet could use a massage... A-alright, I'll do it for you...')

What I'm getting is that the MC had offered to pamper her feet. (I assume through the painting and polishing of her nails. Although, an assumption that a massage might also take place as well isn't too far off.)