gaah I know which one you are talking about, but all I can remember is the penises face lol. I think it might be by Amagi Reno, but not sure.
I found the one I was talking about:
http://www.mangago.me/read-manga/wagamama_na_jewel/ (last chapter)
The only I can think is Chintsubu by Yamato Nase: http://www.mangago.me/read-manga/chinko_no_tsubuyaki/
Maybe it's one of Sakira's.
http://www.mangago.me/read-manga/goshujinsama_to_wanko/an/goshujinsama-to-wanko-chapter-3.html/5/ This story has a devil face on the seme's dick.
http://www.mangago.me/read-manga/ore_no_ushiro_ni_tatsu_na/mh/v01/c006/1.html/pg-5/ This one has a happy face on the seme's dick.
I remember another manga where the uke's dick had like animal faces, one time it was a snake and the other time it was a puppy. But I don't remember the name, sorry. :(
sorry for not replying earlier, but this was not what I was looking for. But this is also everything I'm looking for. Thank you for this! I'm dying from laughter!
I'm trying to find this yaoi. It was part of a one shot (I think). All I can really remember about it is "dick with a face"
Thanks in advance.