"Unforeseen Complications"

As Mitsuki's hands wrapped around his wrists, Takashi felt a sense of trepidation wash over him. He was about to take a step into the unknown, and he wasn't sure what lay ahead. But before Mitsuki could secure the cuffs, a soft voice echoed from the doorway. "Sorry to interrupt, but I couldn't help but overhear that you were about to get started." Takashi turned to see a petite girl with long, curly brown hair and bright green eyes walking towards them. She had a mischievous grin on her face, and Takashi couldn't help but notice the striking resemblance she bore to Mitsuki. Mitsuki's eyes lit up with a warm smile as she turned to face the newcomer. "Ah, Natsumi-chan! Perfect timing. Takashi-kun, this is Natsumi, my little sister." Takashi's eyes widened in shock as Natsumi skipped towards them, her eyes fixed on him with curiosity. He felt like he'd been punched in the gut. Mitsuki's sister? He hadn't seen her in years, not since... Natsumi's eyes sparkled with excitement as she bounced up and down. "Takashi-kun! I didn't know you were going to be here! What are you doing?" Mitsumi chuckled and ruffled her sister's hair. "Natsumi-chan, Takashi-kun is going to be learning about the world of BDSM. He's going to be our new student." Natsumi's eyes grew wide with excitement. "Ooh, that sounds like so much fun! Can I watch? Please?" Rina, who had been quietly observing the scene, stepped forward. "I think that can be arranged. Natsumi-chan, why don't you assist Mitsuki with the equipment while I get Takashi-kun settled in?" Natsumi nodded enthusiastically, her eyes shining with mischief. Takashi felt a sense of unease as he realized that his past was catching up with him. He hadn't seen his sister in years, not since their parents had... Mitsuki's eyes seemed to bore into his soul, as if she could see the turmoil brewing inside him. She reached out, her hand brushing against his, sending a spark of comfort through him. "It's okay, Takashi-kun," she whispered. "We're here for you. Whatever you need." Takashi took a deep breath, trying to calm his racing heart. He had a feeling that this was going to be a lot more complicated than he had initially thought.