【[ts]ga mittsu.】372°C Yuwaku. Available at:

This is a diaper book for Jxx. It’s a manga about a tutor who changes her student’s diaper, watches her pee, has her pee while putting her hands and face on the diaper, uses the diaper as a masturbator, and rubs it against the diaper. (There is no insertion scene.)
(front cover, back cover, 19 pages and a bit of text, afterword, 1 page of extras)