Let's just say I rick rolled all of you

The Basics

Y/N looked up from his computer at the sound of a knock on his door. "Come in." He said, prompting the door to open, revealing his good friend, UMP45. "Hey, 45. Need something?" Y/N asked, scooting away from his computer. UMP45 looked like she was thinking of what to say. "Um... Commander, what is... love?" She asked quietly.

Y/N was taken aback by the response, and UMP45 noticed that. "The thing is," She started. "Ms. Helian was whining about being old and not having a "lover". When I asked her what that meant, she blew me off and started crying." UMP45 explained. Y/N sweatdropped, then cleared his throat.

"Well, love can be... defined multiple ways. For example..." Y/N held up a framed picture of himself UMP45 and UMP9 all posing for the camera. He pointed at UMP9. "Would you say you "love" your sister?" He asked. UMP45 tilted her head. "I don't get it..." She muttered.

Y/N chuckled. "Well, let's put it this way. Love is one way to say that you have a deep connection with someone, or something. For example, I "love" my parents. What is something or someone you have a deep connection with?" He asked. "Well... I guess my little sister." UMP45 replied, thinking of UMP9.

"Well, I can't tell you for sure, but I think it's safe to say you love her. And I'm sure she loves you, as well." Y/N explained. UMP45 hummed in thought. "Okay. But there's more than one way to define it, right?" UMP45 asked. "Correct. Another way is "romantic" love. This kind of love is... even deeper than the love I described before." Y/N started.

Y/N then pulled down a foldable whiteboard, and uncapped a marker. He drew two humanoid figures. One with a skirt, and the other without. "So, to keep it simple, here is a typical heterosexual couple. The man loves the woman, and the woman loves the man. The kind of connection they share is different from love shared by family members, however." He explained.

"How's that?" UMP45 asked. "Well, when a man falls in love with a woman, or vice versa, they get a chemical rush in their brain. This chemical is called Dopamine. It gives the person a feeling of pleasure, which will also activate hormones known as Oxytocin." Y/N explained, drawing both chemicals. He made wavy lines above the figures' heads.

"These chemicals will drive the person to seek romance and/or sex from the person they fell in love with. Sex is in and of itself is another subject I'll explain later." Y/N said, rolling the whiteboard back up. "So, in the most basic explanation possible, love is an emotion that is fueled by chemical reactions in the brain. So, the next time you're with your sister, and you have a deep moment, think about how you're feeling."

...

UMP45 giggled as she tickles her younger sister, who is squealing and begging for her to stop. "Oh, no! This is your punishment for eating my snacks!" UMP45 cackled, and started tickling faster.

After a few more moments of intense tickling, UMP45 gave her sister mercy, and released UMP9 from her arms. UMP9 panted, but had a huge smile on her face. UMP45 smiled back, then plopped next to UMP9 on the bed they shared. Once she caught her breath, UMP9's smile faded, and she embraced her sister.

"I'm sorry, 45... I know you were looking forward to eating them, but I still..." She whispered, trailing off. UMP45 smiled softly, and caressed the top of her sister's head. "It's okay... I won't hate you just for eating some snacks." She whispered back. UMP9 returned the embrace, and murmured, "...I love you, 45."

UMP45's thoughts raced back to Y/N giving his lecture. "The next time you're with your sister, and you have a deep moment, think about how you're feeling."

UMP45 closed her eyes, and felt something in her chest. It was a warm, fuzzy feeling that she couldn't describe. It felt like she had just bit into a sweet cake, even though she hadn't.

UMP45 held UMP9 closer. "...I love you too."