Responses
![](https://pic1.mangapicgallery.com/r/avatar/6f/u508131_50x50.jpg?2)
http://www.mangago.zone/read-manga/yasashii_pantsu_no_nugasekata/
maybe this one? ^^
![](https://pic1.mangapicgallery.com/r/avatar/73/u1619152_50x50.jpg?2)
I think is this one, but I’m not sure
http://www.mangago.zone/read-manga/yasashii_pantsu_no_nugasekata/
The two of them were childhood friends and then the other one distanced himself because he has a fetish of wearing a womans underwear. The uke suddenly got a fever and his sister was out so she couldn't help him so she called the seme and he came to their house to give him a medicine and found out that he's wearing a underwear and plugged the medicine into the uke's butt.