This is the usual transformation heroine x harem book.
A new mysterious transformed heroine
The main character Minoru is kidnapped by Kayane Sasaki and Kotomi Orihime.
While being fully squeezed by two people
The Muzuki family wears a special tentacle suit (combined with sensory deprivation).
I will put it on my body and search for Minoru.
At the end, before the battle… everyone has a harem H!