It had been so long since they’d last shared such intimacy that the eldest twin held no desire for it to ever end. To kiss him without worry, without fear was always the most rewarding. To feel soft lips beneath his own identical ones, left his stomach light and heart full. It allowed him to peer into their love, for what it was— The absolute completion of one another.
Yet as Kaoru pulled away, tiers were left unoccupied and Hikaru did was was only natural to come next. With little conscious mind to what his twin said, mouth was brought down to visible neck— Pressing light kisses and gentle sucks along the flesh.
The sensation of Hikaru’s soft lips brushing against his exposed, sensitive neck made Kaoru moan softly as he tightened his grip upon his brother’s hair, urging him on. “Nn…” He bit his lip in an attempt to stifle his quiet cries, tilting his head to the side as an invitation. Along with the fluttering in his stomach a different, more potent, sensation made itself known; it pooled and coiled itself in his lower abdomen like liquid metal.
He was aroused.
Kaoru could feel himself hardening and automatically jerked his hips forward seeking out the delicious friction he knew his twin would provide. By now he was mumbling—pleading—constantly under his breath, as his hands had now moved down to tug at Hikaru’s belt loops urging him forward so that their hips aligned perfectly. Slim fingers danced underneath his untucked shirt to firmly rest on hip bones fingertips digging in.
"Hikaru. Need- need you. P-please, touch me— Ngh!”
Kaoru let out a noise of contentment as his brother leaned in and kissed him firmly, taking control of the kiss as he had so many times before. He liked it best that way. An involuntary shiver rolled its way down his body as he suddenly felt Hikaru’s fingertips hot on his skin right where his hip bones jutted out above his trousers. Kaoru allowed his own arms to snake around his twin’s neck, pulling him closer to himself as he buried a hand into the silky softness of the auburn hair identical to his own.
"H-hikaru…" he whispered when he finally pulled away breathing heavily. It had been so long since they last… "More," Kaoru pleaded, his golden eyes shining, "please.”
A small shiver ran up Kaoru’s spine as he felt those soft lips graze his ear. “I— I don’t know if I would be any good…” he murmured, lowering his eyelids as he looked away demurely, playing the part of the shy and insecure younger brother perfectly. “You would have to— to tell me exactly what to do… onii-chan.”
"Aaaah~? With you, brother dear? I thought I was your toy.” His lips put on an identical grin to the one his twin wore as he raised an eyebrow.
"What do you want me to do about? I’m just as bored as you.”
[…] After that, the girl said… [I’m sorry. Don’t cry, okay?] I remember how surprised I was when I heard those words. We probably looked like we were about to cry at that time.
Or if you prefer the English dub,
Shiro: And what’s worse, they’re twins, so that makes this totally insectuous!
Tamaki: I think the word you’re looking for is incestuous.