My Friend's Little Sister Has It In For Me! Novel Volume 8 was written by mikawaghost and illustrated by tomari.

It's time for the biggest event of any high school career: the class trip!

With Iroha out of the way, Mashiro's more determined than ever to deepen her (fake) relationship with Akiteru.

Sucks for Mashiro, though--a third girl is now vying for Akiteru's affection! And Iroha's launched into a long-distance offensive to pester him, but will that be enough for her?

With so much trouble brewing, this "relaxing" trip to the hot springs will be anything but!