Two males may not get along together so you will want either 2 females or a pair. You can have them spayed or neutered to avoid any babies--males can be neutered fairly early. I have 2 females, but I will be getting them both spayed as soon as they are old enough because cancer of the reproductive system later in life is quite common but fixing them lowers the chances of this quite a bit.

When you introduce your new bunny make sure to do it in an area that Rain is not familiar with and has not established his territory in yet. Give treats and distractions and let them get the initial rumbling around together out of the way under your supervision. My girls chased eachother and wrestled around a bit (light biting is okay) but they settled down fairly quickly and by that evening they were grooming eachother and snuggling up together.