I'd add that if you do choose to end the risk of this happening again with this same bozo then that means you do NOT communicate with him in any way! Block his number, unfriend, delete! If not, it's evidence for the theory of more "asking for it" or self-victimization. Those of us who have been victims, survived and then thrived can truly relate to taking total responsibility for situations like this but not without full and clear understanding of the perpetrator's responsibility.
Of course, this Bozo will hear loud and clear what you are saying when you truly say NOTHING anymore. UNLESS, he fesses up to perving and abusing in a way that promotes his own healing and moves out of the way for your own.
As for boyfriend, I'm not so sure I'd tell him...yet. I'd need to weigh that out with more and clear understanding of all the dynamics, etc. Telling your boyfriend you may have a pattern of not recognizing potential risks in interpersonal interactions is one thing that can be easily manipulated, misinterpreted and result in avoidable consequences. It depends on more factors than just a black and white opinion. I mean IF the theory of not having strong skills for recognizing risks has any truth, maybe you should get trustworthy feedback about it before you share it so that it's done in a helpful, constructive way on purpose. hmmmm.
The theory/part about the whole story not being revealed is an important piece for the big picture of "you" and even if there is no more to "tell" there's LOADS untold to explore for improving yourself to reduce risks and increase joy in "making life" day-by-day.
Next, if there is a pattern of this in your life (I'd bet my next paycheck there really is), exploring that pattern with a trusted person will reveal ways to grow and as a result change for the better on purpose.
Lastly, as noted before, none of this feedback is suggested to hurt you or put you on the defense. Just fodder for grazing that might prove tasty! PLEASE stay in touch with GS!!!!!