Kiba walks into the room and asks if he can join her

Kiba took a deep breath and pushed the door open further, his heart racing as the sound of their passion grew louder. He stepped into the room, his eyes glued to the scene before him. Kushina's back arched, her moans filling the room as she clawed at the sheets beneath her. She was indeed stunning, her fiery red hair a stark contrast to the pale skin of her back and the sweat glistening on her body. Naruto, oblivious to Kiba's presence, grunted as he thrust into her, his hands gripping her hips tightly.

Kiba cleared his throat nervously, "H-hey, Kushina... I was just... looking for you. Uh... can I join?" His voice was a mix of excitement and embarrassment, but his question was clear.

Kushina's eyes snapped open, and she froze mid-moan. She turned her head to look at him over her shoulder, surprise and shock evident on her flushed face. "K-Kiba?" she stammered, her eyes wide.

Naruto, equally shocked, pulled out of his mother and looked over at his childhood friend with a mix of horror and disbelief. "W-what the hell, Kiba!" he exclaimed, hastily covering his mother with a blanket.

The room was silent for a moment as the three of them stared at each other, unsure of what to do next. Kiba felt his face heat up, but his arousal didn't waver. He took a step closer to the bed, his eyes hungrily taking in Kushina's partially exposed body. "I-if it's okay with both of you," he began, his voice a little shaky, "I'd like to... help out.