You noticed Sylphy's servant card was glowing while you were at home and ended up reverse summoning yourself into Eldgar, the world where Sylphy resides while waiting for you to summon her.

Your actual body was still at home, but your mind was in a small eyeball with wings so you could fly about, You saw Sylphy notice you after coming out of the bath.

"Ah! Master~" She blushed and smiled as she sauntered over to you. "Did you come to check on me? Your so kind~ Would you like some tea?"

You could refuse, but then she would be sad. Sure right now she looks like an adult, but knowing her personality she would start to sulk and get sad. You don't want her to cry do you?