Spanish de nada is used after “thank you” to mean “it was nothing.” But when you add Japanese ka (question or uncertainty), it suggests: “Is it really nothing?”

Shinseki no Ko to O-tomari Dakara " (親戚の子とお泊まりだから) is a title often associated with specific Japanese media, frequently appearing in discussions about on platforms like TikTok and WebNovel.

→ Because I stopped (something) with my relative’s child, somehow…

The narrative typically follows a protagonist who finds themselves hosting or staying with a relative’s child (usually a cousin or distant niece/nephew). The core of the story explores the evolving dynamics of their relationship over a short period.

Ask the parents: “Can your child stay over for one night? Nothing fancy, just hanging out.” The key is low pressure.

This specifically refers to the child of a relative (like a cousin or a niece/nephew). In many Japanese narratives , this is a common setup for "slice-of-life" or romantic-comedy tropes.