"Gotta... Stay... Calm..."
"It's okay, Lambo..."
"Lambo can't!"
"Geez, stupid cow, not again!"
This was the last thing that was heard by Lambo and I-Pin before a swirling cloud of pink smoke engulfed them both.
Tsuna, Gokudera, Yamamoto and Haru stared at the smoke, waiting for it to clear - Reborn, as usual, disinterested. It did disperse quickly enough, but what was revealed made the present half of the Vongola stare even more.
"Wh-whaaaa-?" Tsuna cried, "I-is that -?"
Adult Lambo and Adult I-Pin were absorbed in an activity of their own, and hadn't even noticed they'd come to the past yet. I-Pin didn't wear her usual ramen bar uniform, but a casual Chinese shirt with blue jeans. Lambo was in his usual cow-print shirt, minus the jacket, and with his silv Bovino bracelet. Just one of his horns was attached to the left side of his head. I-Pin's hand was wrapped around this horn, her other hand resting on his shoulder. His own arms were wrapped around her waist. They both had their eyes closed. They were...
Kissing.
Adult Lambo and Adult I-Pin were in the middle of a deep kiss when they got flung back in time, and so they hadn't even noticed.
They finally broke their lips apart, and gazed at each other.
"My kitten... I-"
"D'aawwww!" Haru squealed, "It's love! Bianchi would be so excited!"
Lambo froze up at that name, suddenly realising they were in the middle of a room full of people. "A-ah! Young Vongola!" he gasped, flustered. He quickly straightened his shirt and fixed his hair a little, his cheeks flushed. I-Pin was reacting worse, bright red and almost driven to tears by the sudden embarrassment.
"H-how could this happen? Where are we, Lambo?" she breathed in panic.
"My younger self must have used the Ten Year Bazooka... I'm sorry, kit- ah, um, I'm sorry I-Pin!" Lambo gave a very forced nervous laugh, sweat starting to trickle down his forehead as everybody continued to stare at the pair from the future in shock. There was a painfully long silence. It dragged on and ooooon. The dry air was starting to crack Lambo's lips, so he swiped them with his tongue.
"A-Adult Lambo and Adult I-Pin?" Tsuna asked in surprise.
"So are you two a couple or just hooking up?" Gokudera asked.
"Now, now, Gokudera, that's not the sort of thing you ask," Yamamoto laughed.
"Hahi! You're so cute!" Haru cried.
Lambo cleared his throat uncomfortably. There was another silence. "G- goodness, uh... W-we're a couple... Y-yeah..."
At this moment Reborn finally turned to the pair. "He's not good enough for you."
Lambo opened both eyes. "Now look here, Reborn -!"
Before he could finish, once again they were suddenly shrouded in obscuring pink smoke. When it finally dissipated, the pair were back in Lambo's bedroom in the future.
Lambo sighed and rubbed the back of his head, picking up his second horn from the floor. "My, my, that was embarrassing... I do hope they don't ever mention it to our younger selves..."
Back in the present, little Lambo and I-Pin were in the centre of Tsuna's room once again, fast asleep and resting against each other. The group looked around at each other uncomfortably. The entirety of the kids' upbringing would now be terribly awkward - for all except for Reborn, of course, who still didn't care at all.