[Really, it should be said that David works with him, but the semantics are not important. What's important is that Jesper is suitably impressed — moreover, he's willing to let Nikolai help him explore that part of himself. The nod he gives in answer works for both questions.]

What do you say we work out a schedule for you to come over and use my workshop? You get to hone your Grisha abilities, and I get an extra pair of hands helping me out.

[Everybody wins!]