It had been some time since Tatsuya left and took the latest member of his peerage home. He arrived back at the Occult Research Club, seeing Rias sitting in her chair, looking through some paperwork.
"Need help with anything Rias?"
Tatsuya asks as he takes his leather jacket off, showing a plain black shirt underneath with the sleeves partially rolled up to his forearms.
"No, I'll be fine. It's just some simple things really."
Rias replies while Tatsuya sits down, after a moment he looks around.
"Where's Akeno? Did she head home?"
Rias nods as an answer to his question, he sighs and lays on the sofa. She just giggles before standing up and walking over to him.
"It's adorable how much you two care about one another, and you two have only been friends since we were first-years."
"Yeah well, I did make a promise with her at the end of second-year..."
Tatsuya blushes at the memory with Akeno, Rias simply just smiles and sits beside him, hugging him. Tatsuya hugs back and looks at her crimson hair.
"I remember when she told me about that, I'm surprised neither of you have tried anything yet~"
Tatsuya's cheeks turn almost the same color as Rias' hair, he tries to speak but ends up stuttering, causing Rias to laugh at him before poking his cheek.
"I'm just teasing you don't worry."
Rias smiles before relaxing, leaning her head on his shoulder.
"How have they been? Your brother and sister I mean, I haven't seen them in some time."
"They're well, Ryuu's been busy doing jobs down in the Underworld, and Kagura has been running errands for mother."
"Quite the busy ones aren't they?"
Rias and Tatsuya laugh a little before the latter closes his eyes and summons something; a green acoustic guitar. Rias' eyes light up in surprise and excitement as she sees the guitar.
"You still have it!"
Rias quickly hugs Tatsuya tightly with tears forming in her eyes, Tatsuya smiles and moves the guitar so he can hug Rias, rubbing her back with a bright smile on his face.
"Of course I do, I'm never gonna get rid of it. You gave me this guitar for my birthday two years ago and I love you for that."
Tatsuya's words make Rias tear up slightly more, she looks at the guitar and smiles brightly.
"You're so sweet Tatsu, I see why Serafall speaks so highly of you nowadays."
Tatsuya's eyes widen slightly in surprise at the mention of Serafall, he smiles as he remembers his time with Serafall when he was younger.
"Serafall is a bit of a klutz at times but at the same time she's fun to be around."
He smiles while talking about Serafall before kissing Rias on the forehead and grabbing the guitar and beginning to tune it, surprising Rias.
"W-What was that for?~"
"Because you're like a sister to me, we've known each other for basically our whole lives."
Tatsuya smiles at Rias before beginning to play a tune that Rias recognizes.
"You remember our song... How?"
"What do you mean by 'how'?"
Tatsu snickers before beginning to softly sing, Rias eventually joins in as they continue to relive their times from when they were younger throughout the night. The next morning Akeno come to the Occult Research Club after realising that Rias didn't return home the previous night, as she walks into the clubroom she sees Tatsuya and Rias, both asleep on the sofa, leaning on one another. Akeno pouts but notices Tatsuya's guitar, she slowly gets closer and runs her finger along the top string, causing Tatsuya to wake up and blush immediately as he notices her.
"Good morning sleepyhead~"
Akeno giggled at Tatsuya before looking at the guitar, shortly afterwards, Rias begins to wake up. The trio begin talking about various things for a few hours, eventually Tatsuya looks out the window with a determined look on his face.
"One day, I'll get revenge... For my family."