Before Jeff could think about who to bring into his pocket dimension, the answer came knocking on his door, literally.
"Hey, Jeff. Just came in to pick up your laundry." Jeff looked up to see his father, Mike, with the laundry basket. Mike was a stereotypical middle age dad with a stereotypical dadbod. He was certainly one of the candidates in Jeff's mind to bring to the pocket dimension. Of course, when Mike unknowingly entered the pocket dimension by himself, well, he basically ended up volunteering himself. Welp, guess Jeff should follow his father in, though before he did, he added one more setting to the pocket dimsion. With this setting, Jeff would be able to "sense" if a person belonged to his home dimension in the other dimension or vice versa.
After Jeff stepped through to the other dimension, he noticed that he was already in his Janitor alter ego. There was no transformation this time, though the same couldn't be said about his dad. His father looked like a deer in headlights, looking around in awe and confusion at his new surroundings. Guess the initial transformation was the pocket dimension calibrating what role to give anyone who entered the first time. Mike stuck out like a sore thumb, a random father with a laundry basket in a gym for college students. However, that would soon change as the pocket dimsion started to change him. Mike suddenly froze up as his body began morphing. His change wasn't nearly as drastic as Jeff, but there was no denying that he was growing younger. His face got smoother, and his hair got thicker and changed from black to brown. At this point, Mike had dropped the laundry basket, and it faded away from existence as it hit the ground. The physical changes eventually settled, and Jeff's father was now in his early to mid-thirties. Other than that and the hair change, there weren't that many other physical changes. Maybe he was a bit taller, a bit thinner than he was normally, but that was it, leaving Jeff confused about who his father was supposed to be in this dimension. The confusion wouldn't last long as Mike's clothes began to shift from casual home clothes to nice slacks, a button-up shirt, and a tweed jacket.
Now he knew what Mike was; he was one of the college professors! It was then that new memories began to flood in. In this universe, Mike was a professor who taught art at college. Jeff would often be called to assist in cleaning up after class, and that was how they became friends. He even sometimes was called in to be a model for the class. Still, Jeff had never seen Mike come to this gym before, so he was wondering why Mike was here. Well, it seemed like his questions would soon be answered as Mike was freed from his trance and walked straight to Jeff.
"Ah, there you are, Jeff. Good to see you in your natural habitat." It was a bit weird being in this situation. Back at home, Mike was his dad, but now Mike and Jeff weren't related anymore and were just friends. Having these two separate memories was a bit disorienting, but it was something that Jeff was just going to get used to.
"It's good to see you too, Mike, but what are you doing here?" Mike suddenly became a little shy after Jeff asked his question. It gave Jeff a guess on why he was here.
"W-well, I've heard you were studying to get your personal trainer certification and need a practice client. So, I wanted to ask if I could be your client. I've always been a pudgy kid, and lately, it's begun to get worse. So..." Jeff smiled at Mike's words. This was exactly what he wanted. Guess the Chronivac must have needed to give people a reason to be at the gym.
"Say no more, Mike. I'd love to have you as my practice client and maybe my official client if I pass that exam. Come on, let's start with your measurements and pics, and then we can start working on getting you in the best shape of your life!" Huh, Jeff noticed that he was really excitable in this dimension, wasn't he? He had to wonder if he had a different personality in this dimension. Or maybe he didn't and was just being excited.
"Best shape of my life? Aren't you getting a little ahead of yourself?" Considering this dimension's Mike has always been chubby; the best shape of his life didn't mean much. Though, Jeff's enthusiasm was infectious. Maybe he could get in shape with his help.
"Nah, you got a dream big, right? Don't worry if you stick to my routine, and you'll be looking like me before you know it."
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After that, Jeff began training his former dad five times a week. The exercise routine that Jeff came up for Mike was particularly grueling, but thanks to Jeff's encouragement, Professor Mike was able to complete it. Between sessions, Jeff was busy studying for his certifications, cleaning up both the gym and college and working out himself. It was a hectic schedule, but Jeff was able to manage. The janitor part of him wanted to be a personal trainer so bad, while the normal Jeff was so motivated to work out. Just having this big, beefy body was already motivating, and the thought of having this kinda of body at home was even more motivating.
It wasn't long before two weeks had passed, and Mike was at his weigh-in.
"Woah, that's another 5 pounds loss. You're down 10 pounds in just two weeks. Nice one, dude! Congrats." Jeff patted Matt on the back. Man, personal training was actually quite enjoyable. Being able to change the course of someone's life to make them healthier and fitter was something else. Maybe this could be a life path for him in the future.
"Thanks! I'm feeling great, though, and all my students are pointing out that I'm looking thinner. But it really is all thanks to you and your training. I can't thank you enough." Ah, Professor Mike really was modest, huh? Jeff didn't recall his father being this modest before. Hmmm, speaking of which, maybe it was time to get back to his home dimension. They already spent two weeks here, after all.
"Nah, you worked hard to get here, too. You deserve at least some of the credit. Oh, speaking of hard work, think you can help me out with something?" Mike agreed, and Jeff led Mike to the Janitor's Closet and back to their home dimension.
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The father and son appeared back in their own dimension, with Mike looking a bit dazed. He was holding to the laundry basket he came into the dimension with, which somehow had all the dirty clothes Jeff had in the hamper. It was a strange thing to happen, but Jeff wasn't too concerned about that at the moment. Instead, he was curious if all that exercise really did affect the two of them like he wanted. Looking over at his Dad, yeah, it did look like he lost some weight.
"Oh, Dad. You're looking good. Have you been working out?" Jeff asked to get his father's perspective on this matter. After all, he should know his own body, right?
"Huh? Oh, no, I haven't. Though maybe I did lose some weight by eating healthier?" Mike, for his part, felt dazed for some reason. He didn't remember getting the clothes out of Jeff's hamper, but maybe he just spaced out. Not to mention his pants did feel a bit looser on him than they did a while ago. Uh, maybe he was just feeling tired. So, Mike proceeded to do the laundry quickly so he could rest.
After his father left. Jeff locked the door to his room and took off his shirt in front of the mirror. Yeah, he was looking a little bit more toned than he was earlier. Jeff then went over to the Chronivac and looked over his and his father's stats. Yeah, it did work. Mike lost ten pounds, and Jeff put on some muscle.
Oh, yeah, this was going to be fun. Maybe he and his Dad could go to that pocket dimension once a week to live there for a week or two before coming back. Oh, Jeff could wait for the results to get really rolling and watch how everyone at school reacts to his gains.