Dan Scardino was DEA, undercover as an FDA flunky for the Resurrection Drug. I would guess roughly about 30-33. I don't think he ever says where he's living, but he seems to travel a lot for his job. It sounded like he was in Metropolis only because of the bomber's ties to his dead partner (Jenna). Actually, it sounded a bit as if he was AWOL, or there unofficially. But when Metropolis branch heard he was in town and pulled him in to work for them on several cases.
He has affection for Hawaiian shirts, not that they do anything for him, but he sure looks stiff in a suit and tie. He likes spicy food and Lois's cooking didn't kill him despite him not being invulnerable.
Which either means he has no taste or he's a pretty good liar (I'm guessing the former). He likes to move quickly in relationships because you never know if you'll (or she'll) die, so why take things slow (my thinking is this is a knee-jerk reaction to Jenna dying before they could cement their relationship). He doesn't take 'no' for an answer, despite Lois telling him that she's dating Clark, but that's half her fault for not laying down the law, and part Clark's fault for letting Scardino home in on his girlfriend while he was mourning (blaming himself) for Mayson's death. Scardino is a consummate joker, even taking it so far as to joke while undercover.
I wouldn't say he's a bad guy (i.e. Lex or that Irish guy), just goes after what he wants.
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