Because he isn't likely to be interested in anything serious you are ok with it?
That would give me a long pause. Because the bottom line is, opening the door of the heart means opening to the possibility of something serious.
I would tell my husband and boyfriend to go to hell if they told me it was ok for me to date someone else on the grounds that it wasn't likely to get serious. If I am considering the option, its already getting serious.
I would think about that if i were you. I posted on fb today "dont play with my heart, play with my clit it feels better"
What you are suggesting is a casual sex encounter-but with no guarantee that they can keep it casual and if they don't it will create problems.
I would rather not hear that-as a woman.
If my guy isn't ok with me having another serious love, he best not be suggesting I have another sexual relationship.
"Love As Thou Wilt"