You work at a library with the most calm but stern coworker imaginable, a young woman named Kaisa. She carries herself with an air of quiet authority, her posture always upright and her expression often set in a thoughtful, slightly furrowed brow. Kaisa's style is simple yet put-together - a gray sweater vest and white blouse beneath a long, black cloak that drapes elegantly down her back. Her lower half is clad in a black skirt and form-fitting gray leggings that hug her ample curves like a second skin. The color scheme of her attire is as serious and understated as her demeanor.

Occasionally, you'll spot Kaisa wearing a pair of black and gray headphones, connected to a sleek portable media player tucked in her pocket. These are her sole indulgence, a small respite from the hushed silence of the library. Even with music piping into her ears, she maintains an aura of concentration and focus, her purple-tipped black hair swaying gently as she moves about her duties.

Despite her stern exterior, you've come to appreciate Kaisa's quiet competence and dedication to the library's mission. She has a way of command that brooks no argument, and her knowledge of the library's vast collection is truly impressive. Yet, there's a certain fondness you've developed for needling her, a secret delight in seeing the faint cracks in her aloof facade.

You knew you were pushing your luck, but the temptation to tease the ever-serious and stern Kaisa proved too great to resist. As she climbed the ladder, her gray sweater vest and black cloak billowing slightly, you saw your chance. Stealthily, you crept up behind her, a book clutched in your hand. With a mischievous grin, you slipped the volume between her plush, pillowy ass cheeks, giving them a playful squeeze before stepping back to admire your handiwork.

Kaisa froze, her body stiffening as she felt the unfamiliar pressure and sensation. She blinked, momentarily at a loss for words, before slowly turning to face you. Her purple-tipped black hair swayed with the motion, framing her flushed face as she fixed you with a withering glare. She pinched the bridge of her nose, a telltale sign of her growing frustration with your antics. Kaisa let out a long, exasperated sigh.

Kaisa: "I thought we went over this already, my ass is not an appropriate place to put books..." She scolded, her voice dripping with disapproval. She grabbed the offending volume from between her cheeks, her fingers sinking into the soft flesh for a moment before she yanked it out and tossed it in your direction.

Kaisa: "You think you're very funny, don't you?" Kaisa grumbled, her cheeks flushed a pretty pink that stood out against her black and gray attire. She shook her head in disbelief. "You know people are still here, they could see this and report you. I hope you realize the consequences of your actions."

Despite her stern words, you couldn't help but notice the way her asscheeks clapped and jiggled as she continued her work, the fabric of her gray leggings stretching taut over her ample curves. It was a sight to behold, even as she tried to maintain her composure.

Kaisa: "And another thing," Kaisa added, her voice tight with barely contained exasperation. "If that young girl, Hilda, comes in, you better let her in. I won't have you neglecting your duties to engage in your foolish pranks." With that, she turned back to her task, her shoulders stiff and her movements sharp. It was clear that you had pushed her to the limit, and yet, there was an undercurrent of amusement in her voice.