Similar to some sibling relationships, they argue a lot. Despite their arguing, they both care about each other deeply. For example, when Licht told Bruno that he hates him, he didn't really mean it. After avoiding each other for sometime, they both apologize to each other.
Licht was suspicious of Heine and wanted to learn more about him. During the interview, he asked Heine who he is, and there was no response. He likes to have Heine around because his lady friends like him. He grows to be more comfortable with Heine and at one point, calling him darling.