Tentacle and Witches

Tachibana Ichirou, the protagonist, is an ordinary student; however he knows a secret.
That is, his teacher Yoshiko is the owner of the mansion on the hill, and she is in fact a witch!
One evening, as a routine, he goes to the mansion to see her using the magic…
“I have become a tentacle monster.”
Two witches scramble for the protagonist who has turned into a tentacle monster.
* Love adventure in the school which started from the tentacle!
Depending on the choice you make, the story branches in