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I'm going to insert it now, but it's "just the tip" so it's not sex.

What is this...penetrating my pussy...?"
The teacher's cock penetrates deep into her overly wet pussy.
The sensitive JK, who had been rushed for a long time, faints in agony from the unexpected penetration...
--One day after school, Mima's boyfriend, who she had been dating for the first time, almost forced himself on her, saying, "Just the tip!
In the nick of time, her homeroom teacher, Mr. Kurodo, saves her life.
Relieved, the teacher then asked the naive Mima to tell him what she meant by "just the tip."
He attacks Mima, declaring, "I'll show you what it means to have only the tip of your cock."
Mima's limbs are slowly being caressed by the adult, and although she resists, she begins to feel it.
Mima's body is slowly being fucked by the teacher, and her hole is so tender that she can't help but accept the teacher's cock...

English Webtoon version: https://comiko.net/series/78058/naibu-no-hinto-wa-sekkusude-wa-arimasen