yes, plus also you'll become the talk of the town, everybody will talk shit about you, nobody will respect you, you'll be bullied, denigrated, and most likely will never be able to have a healthy relationship, for 2 reasons mainly,

one, because you'll always be afraid of "what if he finds out?", and what you fear you atract, and you'll focus on the fear and will forget to focus on him and your relationship

two, if he finds out he'll lose any respect he had for you, you may argue it's not right, but the way man are wired, we don't want to know with how many guys you have been with, let alone you had been in a gangbang,

i say don't do it, but it's your choice after all, also ask yourself, what if your parents find out, what will they say? you think they'll be proud of you?