Etan Cohen was introduced as Snot's snobby rich friend in "Bar Mitzvah Hustle". When Steve finds out that Debbie is dumping him for Etan because she wants someone more mature, Steve decides to get even by stealing Etan's most prized possessions: his bar mitzvah gifts. He hatches a complicated scheme that distracts Etan into watching the gift table while Steve takes the money and cards that conveniently fit in Etan's pocket.
Etan falls for the plan and blows a gasket in front of Debbie. Etan accuses Steve of stealing his money unaware that Snot is an unwitting partner. But Snot fouls up the plan and is wrongly accused of stealing Etan's bar mitzvah money. Steve tries to ignore things and hopes they resolve themselves, but Etan reports him to a council of Jewish elders putting his own celebration in jeopardy.
Debbie breaks up with Etan, unaware of Steve's plot, and wants to be friends with Steve again. Roger tries to intervene, but the council decides Snot is to be kicked out of Temple. In desperation, Steve comes clean about the plot but loses Debbie in the process.
According to the DVD commentary, Seth Rogen was originally going to voice Etan. The American Dad! team chose not to use his voice as they deemed that it was too deep and not 'Child-like' enough, so they went with Seth Green.