The rest of the day at the store passed uneventfully. Rena and Dexter closed up shop, and parted ways for home. Both of them lived in the residential district, although on opposite sides of it. Rena chose to walk through the shopping district, as her apartment was right next to said district. Little did she know, she was about to be in the wrong place at the wrong time.
Rena was casually strolling through district, looking for a place to eat, when suddenly she felt something like a burning sledgehammer hit her in the gut. Before she could register what was happening, an uncomfortably warm hand was holding her by the scruff of the neck, dangling her hundreds of feet above the pavement.
"Come out, come out, wherever you are, Overdrive," a voice called out in a singsong style. "Burnout wants to play!"
Burnout was the fire based arch-nemesis of Overdrive, who was a cheetah man given the ability to manipulate kinetic energy. Burnout, meanwhile, was a human man who was basically an evil Human Torch. Rena knew all of this because she followed the real-life superheroes as closely as the comic book ones. She didn't know everything about the heroes and villains, but she knew quite a lot.
"Hold it, Burnout!" A deep male voice called out. Floating a few feet below Rena was Overdrive. He wore a black bodysuit with red highlights, and a red mask covering the upper half of his face. "Put the girl down."
Burnout cackled. "Okay then."
Suddenly Rena was falling. Overdrive made a strangled noise and tried to stop Rena, but he was trapped in a hard light dome.
"Ehehehehehe!" Another voice cackled- the Trapper, a super-villainess who could trap anything. "No so fast, Overdrive. You can't do a thing."
"You're right," Overdrive said. "But my friend can! Valkyrie!"
A pair of strong arms caught Rena. This was Valkyrie, a, well, valkyrie from Asgard sent to help protect Earth. She had blue eyes, golden blonde hair, and wore gold armor reminiscent of Thor's. The friendship between her and Overdrive was legendary.
Valkyrie dropped Rena down near Rena's apartment. "Are you okay?"
Rena nodded dumbly. Valkyrie smiled.
"Good," she said. "Now I must return to the fight!"
Rena stared at where Valkyrie was for a few seconds before she clenched her fists in frustration. Valkyrie was one of the only superheroes she didn't have the autograph of! Rena stomped off into her apartment, her tail swishing angrily.
§.........§
A few hours later is when it began. Rena initially felt woozy, so she decided to take some medicine for it. However, when she got up to get the medicine, she immediately got so dizzy she fell onto her back. Instead of subsiding, Rena's dizziness go worse, until the world was spinning so much she felt like she was going to pass out. Which she did.
Immediately after she passed out, she started to grow- well, part of her did. Slowly, Rena's breasts began to swell, pushing her shirt up higher and higher, until eventually it burst apart. At this point her boobs were the size of basketballs and showed no signs of slowing down. Once again, slowly but surely, Rena's boobs grew.
§.........§
Rena woke up with her face in her fur.
'Weird,' Rena thought. 'I didn't fall asleep like this.'
Rena sat up, and her mind stopped for a second. Where just the tiniest nubs of flesh were before were a pair of breasts that were longer than Rena's arm.
"Holy shit," Rena said. "I just got giant boobs overnight."
Rena then jumped into the air, shouting for joy, before her boobs dragged her back down to the ground. The catgirl braced herself for impact, but never felt it. When she opened her eyes, Rena was floating above the ground, her giant boobs a fraction of an inch from the ground. Rena flipped into a sitting position and landed on her butt.
"I just got powers," Rena said, a bit in shock. "I got giant boobs and the ability to fly. But why?"
Rena remembered the previous day's events. "Valkyrie!" Rena deduced. "She must've had some radiation on her still when she grabbed me. It must've reacted weirdly with her holy aura and did this to me!"
Rena poked her left breast. "I need to come up with an alias," Rena noted. "How about... Cleavage Cat? It's simple, but my boobs have to have some power. They wouldn't be huge just to be huge."
Rena stood up and found that she could tap into her flight power to make it feel like her boobs weighed nothing. She experimentally did a backflip.
"Now, to figure out my powers!"