The grown ass woman acting like a baby and deceiving everybody is getting weird and creepy. There isn't even a good reason for it yet. The boys are head over heels for the baby and she's just an old lady next door. At least in usual isekais the MC got a new life after death and the parents thing is taken as a comedy all the way though. The father here is seriously emotionally dependant on his daughter who is not his daughter, but a full adult in disguise!