Why, yes! It is more sparkling bunny! And smut, at that. Sorry if it's not as good as the rest, but, hey. It's written.
They pulled Soundwave towards their room, only pausing long enough to put the recharging sparklings into Shockwave's little cradle. The bitlet more or less curled around Shockwave, but even Skywarp didn't spend more than a moment cooing over them. They had something to do, something important. Something every Cybertronian dreamed of doing.
Starscream, as trine leader, started it. Thundercracker and Skywarp slipped off Soundwave once the berth-room door closed behind them. They stayed busy with each other, pressing together, running hands against armor, wings, canopies. Starscream took Soundwave to the berth, wordlessly directing him to lay down. Since Soundwave was a telepath, there were none of the awkward moments there might have been. He knew this was the time to submit, to leave the Trine Leadership unchallenged. Soundwave didn't want the Trine Leadership, after all... so he lay down and let Starscream crouch over him and touch.
Blue hands traveled rapidly across the tape-deck's form. Across his sides, over his glass in a move that had Soundwave straining up, and then to his buttons. Soundwave cried out as Starscream pressed the white buttons, and the Seeker smirked lazily. That was what he wanted to hear.
The invitation that had Thundercracker and Skywarp joining the two was a simple twitch of white wings. It would have been missed if they hadn't expected it. Mouths and glossa joined hands on his body, and then Starscream's voice joined Soundwave's cries. Seekers sought pleasure, and Soundwave was helpless to resist, to do more than lay there. That was how Starscream wanted it, time enough for equal pleasure later. He nipped Soundwave's clasps harshly, until the telepath's chest parted and his spark was revealed.
Skywarp moaned, leaning in to lick the spark while opening his chest. Starscream hissed at him, and Thundercracker pulled the youngest away, also parting his his chest. Starscream didn't move to follow, not until Skywarp gave a pleading, warbling mewl. That satisfied the trine leader, and he let his own spark show, gently stroking the straining Soundwave.
"Bonding now," he warned, waiting until Soundwave's nodded. Then Starscream touched their sparks, and only then did Thundercracker release Skywarp. When the four sparks merged, lives combined, past and present and possible futures, and the trine became a mated family. Overload knocked the four mechs offline, recharging close to new mates.