I have to make out with another guy

I [F18] am a theater kid always have been and I’m majoring in it in college now. This summer I’m part of a play that gets credited towards my degree with the time I’m putting in and I love how things are going. My bf [M18] is totally not in the same field at all lol he’s a stem major.

Well I do have an intimate scene with a mutual friend of both of ours, since we are both the leads. We have a brief little “makeout” scene. I didn’t tell my bf because I didn’t think I had to but when he came to the last showing (there’s one more left) he was not happy because he saw me making out with a guy we know.

I tried to explain to him after that it’s not how it appears but idk that it helped his jealousy. I tried to tell him he and I did that scene so many times at this point and literally our relationship hasn’t changed or suffered from it but idk how much it made him feel better.

How do I explain to him I’m not like cheating or something? Will the jealousy go away on its own? Do I just kinda leave it be or do I need to say something else to try and make it easier?