Thersites is infatuated with Mesalina and sees her nonchalance as a challenge. Go see her and deliver his request.
Step 1. Talk to MesalinaA Guardian from Sanctum who is not that attractive but still beguiling..
Step 2. Talk to ThersitesA Daeva of Betrayal. He strolls on the Sky Bridge located between the Divine Road and the Sky Garden in Sanctum. He seems very sad..