I had also forgotten who Van was, although I guessed, since he was a known character, that he was indeed the pope's son since, well, he would be the only one with a reason to see Iris. His status has directly been affected by Iris' trial (which intended to frame Iris, was initiated by the Church following instructions from their faction). Comments have confirmed this.
I wonder what he wants. Iris has exposed the Pope's corruption and there is no undoing that. His status will not be restored. Furthermore their faction is still pressuring Armelia through tariffs, so while the Church has been taken out of the equation, the power struggle is still ongoing. If he's trying to talk to Iris, I'm guessing that it is because he has found no support from his former comrades and has finally realized the true nature of their "friendship". He may have decided that the only way to restore himself, and perhaps dispense some retribution, would be to join Iris. However, perhaps he's simply being used as a spy since he has a believable reason (loss of support from his former comrades leading to revenge) for joining Iris. Yuri has managed to ensnare the hearts of several men, so I would expect she understands that if she starts ignoring someone who has become useless, it sends a strong message to the others that her "love" is based on their value. (Then again, who is left to fool exactly? Berne left a long time ago, Edward is a moron, Van has been expelled from their circle, and I can't recall the last one, but wasn't he being disciplined or something?)