First meeting with my bun. He did this. What does it mean?

I already love Simon! He started cuddling when he first appeared on my hands. Well I hope it's cuddling…
We're about to adopt him, he's about month and a half old. We already bought him but he'll arrive at home at the end of the month. Would be glad to get some recommendations! I may make another post soon with all the questions I have. Of course I want a good friend but most importantly I need him to be happy and healthy.