Is Marumaru-chan based on a book?

Common questions

Is Marumaru-chan based on a book?

Yes. Marumaru-chan is based on the manga Sex-chan.

Who wrote the book Marumaru-chan is based on?

The source is Sex-chan.

Should I read the book before watching?

If you like knowing the full story and characters first, read Sex-chan before you watch. Adaptations often change or cut plotlines, so the book is a different experience even if you've seen the TV series.