I read another story that could have gone either way (Justice or Titan) but considering I've only seen the Teen Titans, I decided I'll put it in the Titan section.
The Flash usually saw the Kid Flash around. Considering time and distance typically meant little to either of them, they would pass each other by, say hi, go about their business. Of course, neither really needed to run around the world, so the times they passed each other were few and far between.
This is why the Flash found it so amusing when the Kid Flash got himself a girl friend. And then there were the times he just didn't want to know.
The first time the Flash passed by Kid was when the Flash was running across the Pacific. Kid was in the center of the ocean and shivering like a Floridian on vacation in Canada, yet somehow his cheeks were red in a way that made the Flash think he was blushing.
"What's up, kid? Pause to tie your shoe, but forgot you weren't on solid ground?" he said with a laugh.
"N-n-n-no-oh," he said, his teeth chattering making it hard to speak.
"Really. Then what is it?"
The Kid Flash looked even more red when he responded, "I, um, j-just g-got a l-lit-tit-tle h-hot is all. N-n-need-d-d-ded t-to cha-cha-chill-llll
The way he responded made the Flash feel like his stuttering wasn't all from the cold. He had a good idea what this was about, but he liked teasing the kid, especially since the Kid didn't like to outright lie.
"Kid, I know it gets a little warm when running, but there are better ways to cool down." Now the Flash had to laugh. Kid Flash's face was priceless. As were his next words.
"I w-wasn't exactly r-running. I, uh, um, uhhh…" apparently getting used to the water. Then, "I had to get out of there! She was just so…! I'm supposd to be a gentleman! I'm a hero!"
The color of that teens face. Ah, teenage hormones at its best.
The Flash stored this exchange as a mental note. The Kid was not going to live this down.
Their next encounter is on a mountain. Flash wasn't sure which or precisely where, but it was dark, gloomy and pretty much everything the Kid wasn't.
Those were the exact reasons the villain Flash just busted put his evil layer there.
"Kid, you do know that some baddie has a layer here, right?"
"No. Sorry." Wow, the kid looked down. The Flash looker around. This was a weird situation, the Kid was always happy. Yet, somehow it lookes like he was moping.
"Hey, c'mon, what's the matter?" Flash didn't know what the relationship was between the bat and mini bat, but he cared about the Kid.
The Kid looked away. "She doesn't like me."
"Who doesn't like you? Everyone likes you." This much was true. Well, the people with a sense of humor at least.
"Jinx. I don't know. She just doesn't like me the way I like her." He mumbled looking down.
"How much do you like her?"
"A lot," Kid murmured.
"Mhm." Flash was thinking. A light bulb flashed. He had an idea.
He bent down and whispered in the Kid's ear.
The Flash continued. His eyes widened, a smile forming on his face. "That might... No, it will work."
"Thank you!" Kid said while running off.
Flash cracked a grin. That's better.
Everyone in the world knew Kid Flash was happy. He made sure of it. You could tell just by looking at him. That is, if he slowed down enough for you to see his face.
It was about the fourteenth time Kid Flash ran around the globe before Flash stopped him.
"Hey, Kid, what's up?"
Kid stopped running only to start flipping, dancing and other things that involved showing excitement.
"She said YES!" He shouted, looking like the happiest man- teen- in the world.
"Who said yes?"
"JINX! She said she'd be my girlfriend!" The look of triumph on his face. Pure happiness was radiating off him. "WOOHOO!"
"Good job, kid."
Kid Flash could no longer contain himself and continued lapping the world.
Interesting enough, the next time the Kid Flash ran around like a nut had nothing to do with Jinx.
The original Titans had just gone to Tokyo and the Kid just had to spread some very true gossip.
"Everyone! Listen! Robin, from the Teen Titans, is dating Starfire! They just got together! That Robin and that Starfire! Go! Spread the Word!"
Then: "News Flash! *chuckle* I'm so funny. Robin, that Robin, the one dating Starfire, wants to kill me. He is now enlisting the help of my girlfriend to get the job done. Oops. Gotta go!"
Flash watched him speed off. Life certainly was more interesting.