Dennis Reynolds from It's Always Sunny in Philadelphia may be the creepiest character on television. Though he started out as a shallow yet somewhat normal ladies' man, Dennis has gotten more out of control as the series went on, revealing himself to be a complete psychopath.

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Though he sometimes has luck with the ladies, Dennis often thinks he is more desirable than he actually is. His short temper and manipulative techniques mean that any woman he does manage to seduce will quickly discover what a monster he is. Here are Dennis Reynolds' most inappropriate pickup lines from It's Always Sunny in Philadelphia.

"How's about you and I go into the back room and I 'change your mind.'"

Mac and Dennis looking curious in It's Always Sunny in Philadelphia

When their various schemes keep failing, the gang decides to start playing to their own individual strengths. For Dennis, he is dubbed "the looks" of the team, a role which he accepts proudly. However, he quickly discovers those looks have limitations.

When Dennis, Mac, and Charlie go to the bank to get a loan for their gasoline scheme, they are unsurprisingly denied. Dennis decides to change the bank worker's mind by unbuttoning his shirt and offering to "change her mind."

"Charlie has cancer."

It's Always Sunny Dennis Mac and Frank

Anyone who has watched even a single episode of It's Always Sunny will know that the Paddy's Pub gang are pretty terrible people. Even as friends, they are completely willing to use each other's misfortunes to their own gains.

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After Charlie tells his friends that he has cancer, they try to cheer him up by getting him a date with the waitress he has a crush on. However, the waitress takes pity on Dennis instead and he decides to sleep with her. To be fair, this wasn't his original plan but it's still a pretty gross that he went through with it.

"We got pretty close near the end there."

Glenn and his fake daughter at the water park in It's Always Sunny in Philadelphia.

Like the other characters on the show, Dennis has only gotten worse over time. He was relatively tame in Season 1 compared to how he is in later seasons. Yet he still proved that there is pretty much no line he won't cross in order to seduce a woman.

When the gang finds a dead man in their bar, the man's granddaughter comes to see the place he died. Instead of feeling sympathy, Dennis only sees an opportunity for sex. He proceeds to lie to the girl and tell her that he was very close to her grandfather, despite never meeting him before.

"I like your look."

Dennis standing next to his son and lover in It's Always Sunny in Philadelphia.

Telling a woman "I like your look" is sort of cheesy but it's not an inappropriate pickup line on its own. However, given where Dennis used the line, it becomes very inappropriate.

Mac and Dennis become involved in the abortion debate and whether pro-life or pro-choice is the right side to fight for. However, they quickly use the situation as a means to meet women. Dennis chooses the pro-choice side as it has more women, but when he is called out for being a creep, he decides it's time to fight for the other side.

"While I don't particularly find you conventionally attractive, I do find you oddly sexy."

When the gang gets involved in the group dating scene, you just know it's going to be a disaster. None of the members of the Paddy's Pub gang are skilled in these situations, but Dennis is confident he will excel.

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Though he has a thought-out plan for seduction, Dennis is unable to hide his creepiness for more than a few minutes. After putting on the charm, he gives what he thinks is a compliment to one girl without realizing it is incredibly insulting and degrading. Things quickly unravel from there.

"I wanna do s*** to you that will make you realize what a worthless, boring piece of s*** your husband really is."

It’s Always Sunny ‘Mac and Dennis Manhunters’

Alhough we are told that Dennis was popular and well-liked in high school, as the series goes on, we get a sense that some of that reputation might have been in Dennis' head. At the gang's high school reunion, Dennis is disliked by many people and seeks revenge on those he thinks wronged him.

In order to get back at his old nemesis, Dennis tries to seduce the man's wife. She is initially charmed by him, mostly because she thinks Dennis is gay. However, he finally loses patience and reveals his entire disgusting plan which, of course, doesn't work.

"We don't want just the two of you, ya gotta bring your girlfriends, that's a requirement."

Dennis at the bar smiling in It's Always Sunny in Philadelphia

No matter what situation the gang finds themselves in, Dennis always sees it as an opportunity to score with the ladies. And it seems like the more inappropriate the situation, the more excited he is about it.

When the so-called "storm of the century" is heading to Philadelphia, the gang decides to stock up their bunker in preparation. Dennis, of course, tries to bring some girls back as well. Though they don't seem too creeped out by the idea, Dennis also can't help but insist they also bring more girls as they are just not enough.

"For the good of the race."

Glenn Howerton as Dennis in It's Always Sunny in Philadelphia

Despite being incredibly creepy, Dennis is usually a pretty confident guy when talking to the ladies. His bad temper is often what screws things up but in one instance, his nerves did actually get the best of him.

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With that storm raging, Dennis confronts the local newswoman he has grown infatuated with. Though he feels as though he has come up with a very reasonable argument, his nervousness makes his ramblings sound even creepier than they actually are.

"I call it the D.E.N.N.I.S. system."

Dennis explains his DENNIS system to the gang in Its Always Sunny In Philidelphia

The fact that Dennis has an intricate and complex system for seducing women should provide enough proof that this guy is seriously messed up. But once he proudly explains the system in detail to the gang, he becomes even more disturbing.

Though Dennis sees this as a sophisticated technique, it's little more than psychological manipulation and emotional abuse. Seeing Dennis attempt to use the situation various times shows how horrible he would have to think up something like this.

"I would like to come in your room. And I suspect that you might say 'no,' and yet I also feel like maybe you wouldn't dare."

Glenn Howerton as Dennis Reynolds in It's Always Sunny in Philadelphia

Probably the most disturbing moment in Dennis' long career of being creepy is his theory about "the implication." In Dennis' warped mind, a boat is the perfect place to seduce a woman because she won't refuse due to the implication that something might go wrong.

We see him attempting to put this theory to the test with a young woman. Though he imagines he's being charming, he is, of course, coming off like a terrifying predator.

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