Erwin considers Eren's abilities to be a vital asset, and it is his words along with Levi's brutal display that ultimately seal Eren's fate as a member of the survey corps.
On Eren's side, Captain Levi of the Survey Corps represents everything he's come to admire and respect: freedom from the claustrophobic outer walls, hatred of titans and a desire to avoid the fate set out for him (when Eren enquires about Levi's past, Petra informs him that he was previously a thug in the underground city).
When the females arrive, sometimes a few weeks later, they go right back to their mates from the previous year.
A female will check out the quality of her old flame's nest by inspecting it, getting in it and lying down.
Getting drunk with friends till dawn, going on dates to the cinema, playing too many video games.
While these might sound like run-of-the-mill adolescent coming of age exploits, these activities took on a rather different form for Jimmin Kang in North Korea.