Hi! Is it one of these?
http://www.mangago.me/read-manga/sweet_as_hell/
http://www.mangago.me/read-manga/kemono_asobi/
http://www.mangago.me/read-manga/kizudarake_no_hakoniwa/
If it wasn't then one of these, then I suggest looking for it through these tags:
http://www.mangago.me/tag/choke/
http://www.mangago.me/tag/kink/
If choking isn't really the focus of the story, then I suggest trying to find it in the bdsm tag:
http://www.mangago.me/tag/bdsm/
I hope you find it!
I want to know too
this is what comes to mind lmfao
http://www.mangago.me/read-manga/tiger_flower/
it's literally in the first-ish chapter (chapter 0/teaser)
Okay so I only remember the smallest part because I closed out the tab and lost it after deleting my history! So basically the this guy was being choked (like kink) by the other guy (I think hes blonde), but it turned out he was actually choking and could die. It is also in full colour (at least I believe it was). Sorry for such little info . . .