Dedicated to: ShannonCataldi for our conversation about this

Sebastian and Barry are twins. They were identical but everyone could tell them apart. Barry was the kind kid who helped everyone, loved school and science and wasn't sporty at all, and Sebastian was the mischievous one who treated girls like they were nothing. They both grew up with Rachel Berry. And unbeknownst to Rachel and Barry, Sebastian harbored a crush on her, and Rachel had a crush on Sebastian and neither of them and Barry knew.

One night Barry sat at the dinner table across from his twin and said

"Sebastian as your twin, back off from Rachel." Sebastian was sat dumbfounded that his own twin brother had said that to him. Said that he Sebastian Smythe had to back off from his love Rachel. Sebastian looked at him and said

"Why should I Bartholomew?" Barry didn't want Rachel to be hurt by his brother and his nature of sleeping with a girl and leaving her the next day, and he said

"Because she isn't one of those girls you can just sleep with and then leave the next morning." Sebastian knew his brother was right, but Sebastian would never do that to Rachel. Sebastian is in love with her. And Sebastian doesn't understand how Barry doesn't see that he's the one that defends her, that he's the one that stopped most of the bullying, knows Rachel's coffee order and even told off Finn for how he treated her. He just doesn't understand how Barry doesn't see it, when Sebastian himself knows that Barry is gay and has a crush on his best friend Thad Harwood, and Barry didn't have to tell him.

Rachel could never tell Barry that she has a crush on his twin brother Sebastian. She is scared of how he will react to it, and it is clear to her that Barry doesn't want her to date Sebastian. Rachel knew of Sebastian's player ways but she didn't care, she couldn't help but fall for him, she has been in love with Sebastian since they were kids. Barry only doesn't want Sebastian to date Rachel because he thinks his twin is too cruel for her. He only wants what is best for his best friend and he knows it isn't Sebastian.

One day after his daily tutoring with Becky, and encouraging her to join the cheerios, as Barry himself loves to help people, and everyone around him, and treats Becky as a person as he knows that is what she wants, Barry walked out of the library with his books and saw his twin brother with his best friend. He was about to walk over to them, to interrupt them, but stopped and saw how his brother treated Rachel with so much kindness something he has never seen Sebastian do with any girl. Barry was even amazed at how Sebastian defended Rachel when Santana started harassing her. It was in that moment he realised that his brother was in love with Rachel, and Rachel was in love with Sebastian. 

Barry watched them for a while longer and realised that he should have never gotten in the way or told Sebastian to back off from her, as he now knew and saw that Sebastian is what is best for Rachel. As Barry walked away from them he walked past Santana was really rude to him. He didn't understand why when he gave up his academic decathlon spot for her girlfriend Brittany who was an alternate for the team, and he was so worried that she would never get to do it, because he knew and understood just how much being on that team meant to Brittany, and the only person to know why he did what he did for Brittany was his best friend Rachel. 

Santana knew that Barry gave up his decathlon spot for Brittany, and assumed that it was because he felt sorry for her and likes her.  Santana pushed past Barry as Rachel and Sebastian intervened the altercation. Barry shook it off and walked away from it all. Barry didn't have feelings for Brittany, Barry likes his brother's best friend Thad Harwood, and the only person to know that is Blaine, and he hasn't even told Sebastian yet, because he's afraid to disappoint his twin. Barry is already considered weird because he likes school, science and not really sporty like his brother. 

Barry sees Kurt get bullied daily because he's gay, and he doesn't want that to happen to him, and he's worried that Sebastian will be disappointed in him because his twin his own twin brother is gay, but he really wanted to tell him. Barry saw Sebastian at his locker, walked up to him and stuttered awkwardly

"Sebastian I-I. H-have s-something to say." Sebastian closed his locker down, looked at his brother and said

"breathe." Sebastian smiled encouragingly at his twin as he took a deep breath and said

"why don't we talk somewhere private, so you aren't uncomfortable with talking." Barry nodded his head and was grateful for his brother as he followed him to an empty classroom. Sebastian sat on a desk and said

"What's on your mind Barry?" Barry took a deep breathe and said

"Sebastian, I'm gay." Sebastian smiled widely and said

"I know. I've known for a while. I was just waiting for you to tell me when you were ready." Barry was shocked and said

"Wait, you knew?" Sebastian nodded his head and said

"I did." Sebastian then stood up, and hugged his brother tight and said

"I'm proud of you for being brave to tell me Barry, and I still love you." Barry was grateful for his twin, and was grateful that Sebastian wasn't disappointed in him like Barry first thought he would be. Barry and Sebastian pull apart the hug and said

"Thank you Bastian, also I saw you and Rachel together after I finished tutoring Becky for the day." Sebastian was worried because Barry told him to stay away from her, and was confused when Barry smiled at him, and said 

"What's with the smile?" Barry shrugged his shoulders and said

"You should ask Rachel out. Something tells me she would say yes."