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Ei-kun is good with his mouth - licking, sucking, and slurping...

"Can I have it in my mouth for the first time?" A languid co-worker's pleasurable oral sex makes her hot and tender deep inside...!
--Mari Yo, an office worker, has never been made to feel good with a "mouthpiece" because of her self-centered ex-boyfriend.
After finally breaking up with her ex-boyfriend, she runs into him on the way home from a drinking party.
Her colleague, Ei-kun, helps her out, but he kisses me pretending to be my boyfriend...!
This is too much, but why does my body react?
He asked me at the hotel, "Will you go out with me? He kisses me at the hotel and kisses me with his hot lips and tongue... Being kissed with his mouth feels too good...!

English Webtoon version: https://comiko.net/series/119576/i-m-in-love-with-mr-hanabusa-s-mouth