As ghost buster Dean Winchester on the WB hit Supernatural, Jensen Ackles can sniff out evil in a heartbeat. But in real life, he’s got a nose for what’s sexy: “I love the smell of shampoo on a girl’s hair,” says the former Days of Our Lives actor, 27. Ackles, a Texas native and one of PEOPLE’s Sexiest Men of 2005, filled us in about what else makes him weak in the knees.

What’s your type?
Me and my buddies say, “Someone who gets it.” Gets sarcasm, gets high-brow humor. Ultimately, someone who you can pal around with and also be intimate with. Someone who can laugh at your jokes – it may sound cheesy, but someone who can be your best friend as well as your lover.

What’s the sexiest thing a woman can wear?
I’m into a casual-dressing girl: blue jeans and a tank top is super sexy. But the sexiest thing on a girl – when I see it I’m like, oh my God – is these little tight boxers. Don’t get me wrong – g-strings are fine – but those cover a little, to where it’s just enough.

Do you and costar Jared Padalecki ever go out carousing?
I do my best to corrupt the little guy, but sometimes I’ve got to respect his relationship (with actress Sandra McCoy).

How about the fan love? Any wild moments?
Sometimes if you’re in the wrong place at the wrong time and you walk out of a bar and a guy’s girlfriend recognizes you and the guy doesn’t like it too much and starts hollering at you – that can get tricky. That happened to Jared and me a couple of months ago.

What’s your hidden talent?
I have a buddy of mine who’s a musician and I play guitar and sing quite a bit with him.

What’s the best present you’ve ever given a woman?
I would say it was a black pearl ring that I designed for her. The pearl I picked up in Tahiti at a market and fished through a bowl full of these pearls until I found my favorite one. The worst gift that I ever gave a girl was a suitcase for Christmas. As in, “I can’t think of anything to give you, but here’s a new suitcase.” Afterward, I was like, “What were you thinking, idiot?”