Experiences with gay guys a straight guy

So, I'm a 30yr old straight guy, never had an experience with guys, never thought about wanting to or fantasised about it, can't say I find guys attractive other than objectively.A gay couple in their 40's I used to work with that I'm still friendly with and in touch via text etc have asked me if I'd be interested in going to their place sometime soon to watch and photograph them having sex etc. and if i was comfortable with it they would be happy to "reward me orally" or more if I like.Now like I said, not something I've thought about in the past and I'm not sexuality attracted to them but I'm putting thought ( actually I'm almost certain I will) into doing it just for the experience, certainly not something I've done before so it'll be interesting to say the least!My question here is what bracket does this put me into sexuality? I wouldn't say it makes me bisexual or even bicurious as I probably wouldn't repeat it but also, are you still a "straight guy" once you've had a sexual experience like this?I know people don't like to be bracketed into a sexuality these days and I'll probably be told to forget about that and enjoy myself but I'm just curious to peoples thought's on it.Please excuse any perceived ignorance, it's not on purpose, I'm just a bit naive to anything that isn't basic heterosexual behaviour.Thanks!