A/N POV:
Today, Min-Joon organized Ye-Joon's birthday party. He had requested you to come and bring Era with you, as Ye-Joon insisted he wouldn't cut the cake without her. Despite knowing that Jimin would also be there, you decided to go.
"Era! You finally came!" Ye-Joon exclaimed as soon as he saw you and Era entering. You parents are smiled, seeing the bond between your children.
"I missed you. Why didn't you come last weekend? I'd been waiting for you," Era complained, pouting at Ye-Joon.
"Oh, you were waiting for me?" he asked, and Era nodded.
"I'm genuinely sorry, Era, but I have something I promised you," Ye-Joon said, causing Era's eyes to light up.
"Really?" she asked eagerly.
Ye-Joon nodded, smiling as he took her hand, and they ran inside together.
"Children, be careful," Hye-Jin called after them, her voice filled with a mix of amusement and concern.
"Ye-Joon, where are we going?" Era asked as Ye-Joon pulled her along.
"I have something for you," he replied shyly, helping Era to sit on the sofa like a little gentleman. She giggled at his manners.
Ye-Joon took out two hairbands, one blue with a sunflower print and the other pink with the same pattern.
"What are those?" Era asked innocently.
Lowering his head shyly, Ye-Joon put the blue band on Era's wrist and said, "Can I become your boyfriend?"
Era looked at him in confusion. Meanwhile, they were unaware that someone was watching their sweet moment. It was Jimin, who had been passing by the door but stopped when he heard voices. He couldn't help but enjoy the innocent interaction.
"Boyfriend? What does that mean?" Era asked innocently. Jimin chuckled at her naivety.
"Ah... Boyfriend means that if I become your boyfriend, I'll always be with you. My dad is a boyfriend to my mom, that's why they're always together."
"Really? If you become my boyfriend, we'll always be together?" Era asked, her eyes wide with curiosity.
Ye-Joon nodded. "Okay, then you're my boyfriend," Era accepted.
Ye-Joon shyly put the pink band on her wrist, and she reciprocated. "Now that you're my girlfriend, you're not allowed to make friends with boys," Ye-Joon declared authoritatively.
Seeing his domineering nature, Jimin couldn't help but press his lips together to stifle a laugh.
"But you said you're my boyfriend, what's this girlfriend now?" Era asked, puzzled.
Ye-Joon held his head, clearly exasperated by the innocent little beauty. "You don't need to understand. When we grow up, you'll understand."
Era gave him a puzzled look, silent in her confusion. Ye-Joon chuckled and, caressing her hair, said, "You're so beautiful."
He watched them in awe, reminded of Y/n and his, and how everything was simpler between them. Ye-Joon caressed Era's cheek and kissed her softly.
Jimin's eyes widened, a pang of jealousy surging through him as he saw Ye-Joon leaning in to kiss Era's lips. Unable to bear it any longer, He pushed open the door.
"Hey, what are you doing?" he asked, his voice sharper than he intended. Ye-Joon quickly backed off, his face turning red.
"Nothing," he mumbled, grabbing Era's hand. "Come on Era, let's go."
