Do I tell them?

Sadie

I'm still questioning, but I'm 99% sure I'm pansexual. I'm not in a relationship right now, but for future reference, if I'm in a relationship with someone, is it common courtesy to tell them my sexuality?

I mean, I just wonder if I were to get in a relationship with a guy, would I tell him I also like girls? Or would that just make things messy? Same question vice versa.