Slughorn/Minerva
It didn't strike Horace odd that Minerva wanted to speak with him face to face. He preferred that type of communication over the journals. However, he wasn't prepared for her request.
Horace sat still for several moments, his hands clutching the arms of the chair. "I have caught wind of the society," Horace admitted. "Join you? What use would you have for an old man like me?" Horace wanted to join... he wanted to do anything he could to repent for telling the inquisitive Tom Riddle about horcruxes. He just wasn't sure how he could help.