[F23] Birthday hogtie that turned into my first time with a girl — and my boyfriend watched the whole thing

My boyfriend’s birthday was coming up and I asked what he actually wanted. He didn’t hesitate. He wanted me tied: naked on the bed, rope around my thighs, wrists bound so I couldn’t do anything useful with my hands, ankles pulled in. I said yes. I’d been curious about the rope for a while and I trusted him.
That night I got on the bed. He took his time with the knots. Coarse rope around my left thigh, then my right, wrapping my wrists so they sat against my legs. Another set of wraps pulled my ankles closer. I ended up on my side, one knee bent high, the other stretched, tits out, necklace still on, completely unable to cover myself or push anyone away. He checked the circulation, kissed my forehead, and told me I looked perfect.
Then he slid a blindfold over my eyes.
“Stay like that,” he said. “I’ll be right back.”
I heard the door. Footsteps leaving. A couple of minutes of just the bed and my own breathing. Then two sets of footsteps coming back in.
My stomach dropped.
“Who’s with you?”
He didn’t answer. He just sat on the edge of the bed and started untying the blindfold. When it came off I was looking straight at my flatmate Jess.
She’s lived with us for eight months. We get on. I’d drunkenly told my boyfriend once that I was curious about girls, that Jess was pretty, that I’d wondered what it would feel like. I never thought he’d actually do anything with it.
Jess was in a t-shirt and nothing else. She looked a little nervous too, but she was smiling.
“He said you were curious,” she said. “And that it was his birthday. I said I’d try if you were okay with it.”
I was still tied. I couldn’t hide. I felt my face go hot and my pussy get wet at the same time. Nervous and excited is the only way I can describe it.
My boyfriend sat in the chair by the bed and didn’t touch either of us. He just watched.
Jess climbed onto the mattress. She started at my mouth — slow kiss, her hand on my cheek — then worked down my neck, over my tits, sucking one nipple while she pinched the other.
When she got between my bound legs she didn’t tease for long. She licked straight up my pussy, then pushed her tongue inside me. I tried to close my thighs and couldn’t; the rope held them open enough for her. She ate me like she’d been thinking about it. Her nose against my clit, two fingers sliding in while she sucked. I came the first time with my wrists straining against the rope and my boyfriend’s eyes on both of us.
She didn’t stop. She flipped me a little more onto my side so she could get at my ass. Tongue on my hole, then inside it, messy and filthy while her fingers kept working my pussy. I was shaking. I kept looking at my boyfriend.
Jess made me come again with her mouth on my ass and her thumb on my clit. After that she crawled up, kissed me so I could taste myself, and asked if I was okay.
I was. More than okay. After that my boyfriend went behind my head and I could feel how hard he was, Jess looked at me with the can I look and I nodded. She sucked him off and made him cum all over my stomach. Jess then cleaned it up with her tongue.