Responses
I don't see an issue with that, it would be bad if MC was the one blushing towards the child looking person, but the other way around is fairly common. Allot of people have crushes on people older than them, Especially children, it is kinda cute that way, but extremely creepy the other direction. As long as MC does not develop any romantic/creepy feelings, I think it is fine
Everytime I see Yuna beside the mc it gives me the ick. Like there's A LOT of curses to pick from and you picked being not able to physically age? WHATS WORSE IS THAT SHES CANT AGE AND BEING STUCK LOOKING LIKE A CHILD? I mean she's mentally mature but like??