Is it ok for two gay partners to have a gay roommate?

I travel quite a bit for work (airline pilot) and am consequently away from home about half the month. My partner and I have been serious for almost two years now and have been sharing an apartment for almost a year. I’m thirty-one and he’s twenty-five. We’re extremely close but we both tend to have our insecurities. One of his close friends is a waiter and has been having a hard time affording rent and just getting by. My partner has run the idea by me of letting his friend rent the spare bedroom in our place. Normally I wouldn’t mind. However, his friend is also gay. He tells me that nothing romantic has ever gone on between them in the past other than a long friendship. My concern is that his friend is younger than me and although I consider myself fairly attractive I believe his friend to be more physically attractive than both of us. I’ve met him before and he’s a genuinely nice guy. Considering my job, am I letting jealously and irrational though get the better of me? Is my concern unreasonable? I trust my partner, but in a sense we’re all animals and have that side that might let lust get the better of us. Should I object to this proposal or let his friend crash with us a while?