He can edge himself closer than you can most of the time so it’s hot to make use of that sometimes.
Uncage him and snuggle up next to him. Kiss and touch him, especially playing with his nipples, but don’t touch his cock, not at all.
Hopefully it’ll get nice and hard by itself, but if it doesn’t, well then you tease him, ‘Maybe it doesn’t want to get played with, shall we just put it back in the cage and see if that helps?’ That will almost definitely get him hard. If it doesn’t, consider doing that!
But the fun challenge is to try and use your words to get him hard, with no contact.
Tell him how hot it is caging him, tease him about the size of his cock, or how long it’ll be till you let him cum. Maybe get a vibe and start playing with yourself too, and just moan in his ear.
At some point he’ll ask you to play with his cock, say no, say you want to watch him today. Maybe pour some lube on it and then start watching, tell him you want him on the edge for as long as he can handle it.
Whisper in his ear how you love he can’t do this without you now, how you love knowing his cock is yours, how all those times he used to get off without you are gone forever, and all his sexual energy is focused on you.
As he gets closer start to be a bit meaner, tell him he’s not allowed to cum, that you like his balls full and aching. Tell him if he cums he’ll have to eat it, and you’ll lock him up for a whole month without release.
Make him beg, first let him beg to be allowed to cum, say no, then see if you can make him beg to ruin it. Say no. Then tell him you want to hear him beg to be denied. ‘Beg me to not let you cum’ ‘Beg me to lock your little dick back up and lick me to orgasms while you stay denied’.
It’s so hot when he says it.
It’s even hotter when he does it.