Damn I am here for the name don't mind me!! (づ￣ ³￣)づ
are you maybe talking about this? if it's this one, it doesn't have a translation yet but it's on boomtoon https://www.mangaupdates.com/series/vyhagtc/rabbits-ejaculate-in-3-seconds
Is it "you who wants love"?
there's also this but the seme and where the romance takes place doesn't fit your description but it's a buff bunny x buff dog story https://www.mangago.me/read-manga/safety_first_yunbyeol/
The bottom is a black rabbit/musclar man and the top is a soft/quirky looking wolf/man office romance