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Takuya Aihara is an average junior college student with one big flaw: he's a weakling. The girls around him push him around at every turn, his teasing step-sister Natsumi, the genius chemistry club president Mami, and especially his beautiful childhood friend Asuka. He can't assert himself, and then one day he spills a mysterious chemical on himself in the chemistry room and wakes up as a girl.

X-Change is the original of the long-running Crowd series, the title that made the OTC gender swap premise an entire subgenre. The MTF transformation drives every scene, with Takuya navigating school, his step-sister, Asuka, and his own confused feelings inside a body he didn't ask for.

2DCG art, Japanese-game school-setting framing, multiple endings, and a tag list spanning corruption, lesbian, futa/trans, BDSM and virgin. A reference-tier gender bender porn game that defined what a Japanese TG porn game looks like.