Leslie Winkle

Arrogant and condescending – Leslie is described as arrogant, condescending, and manipulative. She is convinced of her intellectual superiority and doesn't hesitate to let others know, especially Sheldon .

Manipulative – In her relationship with Howard, she uses sex and access to lab equipment as bargaining chips to control him. She admits she can only be happy if she is the one in control .

Direct and unfiltered – Leslie says exactly what she thinks, regardless of social conventions. She calls Sheldon "dumbass" at every opportunity and doesn't mince words about her colleagues .

Serious about her work (when she's not cooking with it) – Despite her inappropriate use of equipment, Leslie takes her research seriously. She is capable of solving problems Sheldon himself cannot solve, which deeply irritates him .

Sexually liberated – Leslie fully embraces her sexuality. She offers Leonard no-strings-attached sex, tells him she'll be "good till New Year's Eve," and has a purely physical relationship with Howard. She is described as unapologetically promiscuous .

Intolerant of incompetence – She cannot stand people she considers intellectually inferior, and she doesn't hesitate to let them know. She is particularly harsh with Sheldon, whom she considers an "arrogant, misogynistic East-Texas doorknob" .

Capable of making Sheldon stutter – She is one of the few people who can make Sheldon stutter. Her mere presence on an opposing team is enough to shake his confidence .

Evolving (a little) – In Season 9, she shows she has matured, but she ultimately remains true to herself, which is reassuring for fans .

Episodes with Leslie Winkle often revolve around:

The rivalry with Sheldon – Leslie is Sheldon's "archenemy." She constantly throws him off balance, whether by solving his equations, insulting him, or joining the opposing team in the physics bowl. Sheldon hates her as much as he fears her .

Relationships with Leonard – Leslie and Leonard have a complicated relationship. She first rejects him, then uses him to satisfy her sexual needs, then attempts a real relationship with him, before dumping him because he doesn't support her belief in loop quantum gravity .

The "friends with benefits" relationship with Howard – Leslie begins a purely physical relationship with Howard, whom she controls by offering equipment and trips. Howard develops feelings for her, but she eventually dumps him over the phone .

Inappropriate use of lab equipment – Leslie is often shown using lasers and liquid nitrogen to prepare food, which is a recurring source of humor .

The physics bowl – Leslie joins Leonard, Howard, and Raj's team after Sheldon is kicked off for his showboating. Her presence throws Sheldon off, and they win the tournament .

Later appearances – Leslie reappears in Season 9 for Sheldon's birthday, where she shows she has changed, but ends up reverting to her old habits by insulting him .

1. With Sheldon

Sheldon: Leslie, your presence in this lab is an insult to the scientific method. Leslie: And your presence in this universe is an insult to evolution. So we're even, dumbass. Sheldon: (stutters) I... I haven't stuttered since high school. Leslie: That's my superpower. Every time you open your mouth, you get stupider. It's fascinating to watch.

2. With Leonard (after their first night)

Leonard: So, uh... are we gonna do this again? Like, an actual date? Leslie: Leonard, I used you to satisfy a sexual urge. It was pleasant. You're a "magnificent beast." But my appetite is covered until New Year's Eve. Don't ruin it. Leonard: New Year's Eve? That's six months away. Leslie: Exactly. Enjoy your celibacy. (she turns back to her equations)

3. With Howard (friends with benefits)

Howard: Leslie, can I come with you to Geneva? To see the LHC? Leslie: You can come if you do exactly what I say. No feelings, no expectations, no "I love you." Just sex and physics. Howard: Deal. Leslie: Good. And Howard? If you develop feelings, I'll dump you over the phone. Like an old sock. Howard: (swallows) ... Understood.

4. With Penny

Penny: So, you're Leslie? Leonard told me about you. Leslie: Ah, Leonard. He talks about me? That's cute. He talks about you too. A lot. It's kind of pathetic, actually. Penny: What do you mean? Leslie: Nothing. Just that you're the girl he can't have. And I'm the one he had. And who dumped him. See the hierarchy? Penny: (awkward silence) Leslie: Have a nice day, blondie.

5. With Bernadette (Season 9)

Leslie: Bernadette, right? I heard you married Howard. Congratulations. Or condolences. I never know. Bernadette: It's congratulations. And you're still... Leslie? Leslie: Always. Still brilliant, still rude. Some things don't change. Bernadette: I heard you slept with Howard. Leslie: Yes. Several times. He was... energetic. But not enough for me to stay. (smiling) No offense. Bernadette: (forced smile) None taken.