I'm all for the mind battle, it's actually pretty cool, but please, think of the collateral damage and don't play with the innocent girl's feelings....
That turning into a human by removing the cat-ears headband took me by surprise. Also wondering if the landlord’s kid is a ’he’ or a ‘she’. In a previous chapter, the kid was referred to as a ‘he’ but I do know that japanese has a non-gender specific pronoun that translators have some trouble smoothly wording into english.