Kylan is a batarian who hangs out with two other batarians in the entry area of the Afterlife Club on Omega.
If Commander Shepard approaches them, they react aggressively. Shepard can either convince Kylan that they aren't worth his time by drawing a gun, or forcibly threaten Kylan and his friends instead. Both choices reveal Kylan's relative cowardice. Shepard can also avoid any confrontation by saying they are just passing by, prompting Kylan to smirkingly tell the Commander's group to keep moving.
In all outcomes, Kylan and his friends will head into the club and not cause any further trouble.