This unnamed man was Debby's Drama Teacher. In S4E4, Curtis finds a DVD in Debby's flat which shows Debby in a drama class. Following Debby's convincing monologue in the role of Lola, her teacher compliments her performance and tells her to re-watch her performance on the DVD and persuades her to "become" Lola. Shortly afterwards the storm hits, giving Debby her power of Personality Rewrite, in which she believes she is in fact Lola. It is unknown if the drama teacher also gained a power or if he remains alive.