I was hired to shoot a video, not to have a threesome, but i liked it and now it 's my job too

I have been working as a cameraman for several years, making videos of weddings, birthdays, events, meetings, but never had done anything like this. i was called a couple to ask for an intimate video, i was told to come home to talk quietly, i had very little work this week, so i went. they were an asian couple, quite young. the girl was very sexy, we hit it off right away. they said they wanted to do the video in the bedroom having sex, and i did. when he took the clothes off from her, i couldn't avoid getting an erection. i wanted to be the one to suck her body and touch her pussy. i was there, working, when really wanted to join in the fun. she knew it, i noticed that she was looking at me. i started to touch myself with my free hand. then i pulled out my cock and started to masturbate in front of them. so far it's video, because that's the moment when i was invited to join the party.