It’s been a few weeks since the protagonist started living with Leviola, a succubus. One day, just as the long vacation was coming to an end, a new succubus named Milis appeared from a magic circle that materialized on the ceiling.

“I can really smell your high-quality vital energy… Won’t you become my cum slave…?”

No sooner had she said that than Milis began sucking on the protagonist’s penis! Of course, Leviola wasn’t about to let that happen.

The protagonist’s semen belongs to her, his older sister… She glared at Milis, determined not to give it up under any circumstances. Will the protagonist ever be able to return to his peaceful life…?

[From official site]