A 2009 study at Oklahoma State University confirms what legions of men have sworn since the beginning of time: women are twice as likely to want a relationship with a man who's already taken. (Gross.) What about an already taken man is appealing? More than taken, he's legally bound to another woman.

 While we can't speak for all women on those allegations, we've crafted a charming guy checklist that we think works as well, if not better. Men: Don't forget these must-have items the next time you go out on the town looking for love, and ladies: make sure to check his left hand.

Here are 6 charming things men do that women simply can't resist, according to psychology:

1. Give good eye contact

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We're aware of how basic this sounds. Almost in the same league as "say hello" but we cannot stress enough how often this simple social pleasantry is butchered. If you're new to this, start slow and look us in our eyes, not at the girl walking up the steps behind us. 

Eye contact is a potent stimulator of affection. A 1998 study published in the Journal of Research and Personality in which two strangers were asked to gaze into each other’s eyes for two minutes found that this was enough in some cases to produce passionate feelings for each other.

2. Wear a killer scent

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Please approach cologne like you would flattery. Laying it on thick seems tacky and don't go for cheap and obvious. A light spritz is all it takes to let us know you've entered our space.

3. Back off if we give you a signal

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We suddenly have to pee. We text and a friend appears. We scoot away, mentioning a purse, bag, bartender, ATM, or a slice of pizza that needs to be found/retrieved/eaten. We want to leave. And we're trying to be polite. 

Research published in 2016 suggests that women find respecting nonverbal signals attractive because it indicates a potential partner's ability to understand and respond to their emotions, demonstrating qualities like empathy, attentiveness, and good communication skills, which are highly valued in relationships; studies have shown that open, expansive nonverbal displays, like good posture and direct eye contact, are beautiful as they signal confidence and potential dominance, further increasing a person's perceived desirability as a mate.

4. Lend an attentive ear

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We want to know all about your musical gripes with the Arctic Monkeys and how your neighborhood has the best Thai in the whole city. Really. We do. But if we're rattling on about the epiphany we had while backpacking through Greece, pipe down and listen. Refer to #1. Wait for a pause, another beat for good measure, and then politely work in your opinions about hostels in Amsterdam. 

5. Sport a big-boy accessory

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Spending a month's pay on a gold medallion isn't going to charm the pants off us. But never underestimate the brownie points you'll earn when we surreptitiously notice a nice, understated watch. Or a pair of shoes, a slick jacket, or a nifty haircut. Just a sprinkling to let us know you've progressed beyond backward baseball caps and basketball jerseys. 

Initially published by researchers at the University of Glasgow, College of Science & Engineering, this study compares the personality traits associated with wristwatch wearers and those who do not wear a wristwatch. The initial research found that "participants who identified themselves as regular watch wearers rated themselves as significantly more conscientious when compared with controls. We also observed that watch wearers scored lower in extraversion, agreeableness, and openness but higher on emotional stability."

6. Open doors

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Chivalry isn't dead! A guy who opens doors for a woman shows he was raised well. In a 2019 study on female mate preferences, researchers said: “Evidence shows that many women—even those who desire egalitarian relationships—want a man to be chivalrous by, for example, paying for dates and opening doors for them.”

This indicates that women generally prefer men to open doors for them. Women appreciate specific traditional gender roles that exhibit chivalry, which can be perceived as positive signals for mate selection. Many women can consider it a positive sign when a man holds the door open for them. 

Melissa Noble is a freelance writer and blogger who writes about love, relationships, and trending news stories.