Toilet-bound Hanako-kun manga volume 5 features story and art by AidaIro.

Nene Yashiro serves as the assistant to the School Mystery Hanako-kun. When she is invited by enigmatic playboy Natsuhiko to a mysterious tea party, she meets Hanako-kun's "girlfriend" and his "little brother"...!? On top of that, she learns that one of the Seven Mysteries is mixed in with her classmates...

Toilet-bound Hanako-kun manga volume 6 features story and art by AidaIro.

Through the workings of the School Mystery Clock Keepers, Kamome Academy's entire student body is covered in wrinkles!? To restore peace to the school, Hanako-kun teams up with a certain someone. Just when they thought the case was headed to its conclusion, the secret of Hanako-kun's assistant Nene is brought to light! What could it possibly be!?

Toilet-bound Hanako-kun manga volume 7 features story and art by AidaIro.

Nene has suddenly been dragged inside a mirror, where she meets the spirit of a young boy calling himself Mitsuba. As they try to escape, the threat of School Mystery No. 3, the Hell of Mirrors, draws ever closer. Nene may have finally gotten herself into a mess that even Hanako-kun can't save her from-but will someone else come to her rescue...?

Toilet-bound Hanako-kun manga volume 8 features story and art by AidaIro.

It's been three days since they returned from within School Mystery Three, the Hell of Mirrors. To cheer up the depressed Kou, Nene heads to the Boundaries' Tanabata festival. She was supposed to be enjoying the festival with Hanako-kun and Kou, but suddenly she finds herself fifty years in the past-and happens to meet the living Hanako-kun there!?