Are there any BL with an asexual MC??

I would like to know too. All About Lust has an asexual side character, but that's really the only one I've come across and he doesn't make enough appearances, in my opinion. ):

http://www.mangago.zone/read-manga/usagi_no_mori/ it's mentioned and questioned but the story itself isn't complete so we don't know what will happen or if the character actually identifies as asexual. but it's definitely implied

All about lust has a character who plays a big part in the plot who is ace, but he isn't the mc tho

Eh, it’s never canonly said but they did say he just likes having a relationship without sexy time.

http://www.mangago.zone/read-manga/sexless_am/