If he's property then what you want goes and his wishes are irrelevant. It's entirely up to you if you take multiple slaves, if you let him play with others, and so on.

The real world is usually more complicated than that, but you should still set red lines with anything you aren't comfortable with. Many Dommes would never share their subs, and that's totally fine.

If you want to dip a toe into it, you could for instance try taking him to a club and letting him approach someone of your choice to see if they want to play with both of you. A public setting and a stranger makes it easy to call a halt if you aren't enjoying it. But you definitely shouldn't feel obliged to consider his request at all.