Shiro's reaction to his s/o handing him a bag and saying "I saw this and it made me think of you" it's a shirt that says #1 space dad. S/o is wearing one that says #1 space mom that Lance and pidge picked out.
I wasn’t sure if you wanted this to be headcanons or a scenario, but I’ll write it more as a scenario sort of thing. I hate how vertically large that gif is, but it’s the only one I could find that would work with his reaction.
Shiro was having a perfectly normal day. So, he knew something was bound to happen. Staying alert, he turned immediately when he heard the sound of a door behind him. When he saw his beautiful girlfriend walking into the castle’s lounge, he couldn’t stop the smile that spread on his face. He didn’t even notice the bag she carelessly hid behind her until she held it out to him.
“I brought you a present,” she offered him with a smile of her own. “I saw this and it made me think of you.”
“Oh? I wonder what it could be,” Shiro replied, taking a seat on the couch behind him. She followed his actions, leaning onto him slightly as he carefully opened his present. “It’s not even my birthday, so why-”
His voice stopped when he saw what the present was. He was fine with the fact that it was a shirt. But Shiro’s expression deadpanned when he read what the white graphic T-shirt said. “#1 Space Dad.”
His eye twitched as the nickname befell him again. It was only followed by a sigh, as he decided to accept what seemed inevitable at this point.
“Let me guess. The others were with you when you bought this,” Shiro said, side-eyeing her.
Her giggle was enough for him. “You wanna see the best part?”
“What could possibly be better than this?” Shiro asked.
He watched as his girlfriend stood from the couch and opened up the black hoodie that she had had on. When he saw what she was wearing underneath, Shiro couldn’t help but laugh. “#1 Space Mom.”
“Lance and Pidge picked them out actually,” she explained, holding the shirt down so it could be read properly. “Personally, I’m quite fond of it.”
Shiro rose and wrapped his arms around her. “Couple tees? Didn’t think you were the type.” She shrugged, but nuzzled her cheek into his chest. He chuckled, his chest vibrating as he did so, and kissed the top of her head. “I suppose I’m quite fond of it too, as long as it shows that you’re mine.”
“And you’re mine.”