Before we start this story off, let's call this burglar, Bob.
When Bob fully zips up Jeff inside him, he heard Jeff moan in pleasure that he is in joy of being worn and squirms. "Woah, this is so freaky.... But I like it!" Bob says as he decides to kill time and flop on Jeff's bed and jack it inside Jeff. Bob also feels Jeff wriggles his crotch area, rubbing Bob's crotch and moans in pleasure as Jeff continues and both of them are in a state of total arousal. Bob helps Jeff by placing a hand on their crotch and rubs in circle motion around his dick driving both of them more into arousal.
Outside of Jeff's house, Jake is almost home from self-defense class and is tired out from today/tonight's session. "Ooh.... I think I'm gonna play some League after this." he said in exhaustion as he slowly reaches the front door. Jake then unlocks the front door while Bob, in Jeff's room still jacking off in Jeff is still in deep arousal still not aware of Jake's presence as he enters the house and immediately drops his stuff and closes the door gently. He then kicks off his shoes and starts walking to the kitchen for a drink. When he reached the kitchen, he noticed broken glass and the door open which made him be on the alert if the thief is still around. A moaning sound came from upstairs. "That's in Jeff's room!" Jake said to himself as he silently ran up the stairs and hear moaning and Jeff's bed creaking. He hid beside Jeff's door and see the thief wearing Jeff (Jake does not realize it yet) jacking himself off. "Ugh, that prick. Wearing my younger brother's secret hobby of a costume." he said to himself under his breath and busts in the door. "HEY ASSHOLE!" Jake yells at Bob who snaps out of his arousal and turns to his side to see an angry Jeff's older brother in a martial arts stance. "Oh shi-" he sentence was cut off until he was kicked in the face and immediately blacks out.
Bob then slowly wakes up, only to find himself naked but with someone's shorts on and his hands tied behind his back. He grunts and struggles trying to break free. Then, he saw the gold zentai to Jake's right, and the chronivac pointed at him. "Give me back my suit and that device! They're mine! and " Bob yells in anger at Jake in Jeff's form. Jake said, "'your' suit and 'your' device? I think they belong to my family. And you were wearing my younger brother that you soiled by your own shit." Bob was confused, "What? But that's just a suit." Jake sighed, "Well, you're gonna know why I said that you thief." He then typed in what he's going to be permanently as a living zentai suit and then initiated the transformation sequence. Then Bob feels weird and looks at his normal skin color darken into a pitch black color on his stomach and spreads. He then feels his flesh turn to spandex, his hair and body hair soon fall or disappear in clumps. "Wh-what's happening to me?!" Bob said bewildered as more of the black spots on his skin spread and turn to spandex. Then zipper track and two zippers form on his back running from his lower back to the back of his head. His toes merge into one leaving him toeless. And then he saw his dick and balls soon shrink inside his crotch leaving it smooth. "Noo! Not that!!" he panicked. Jake chuckles, "Don't fuck with my family even if they did become an inanimate object!" Soon, Bob feels his ears and nose sink into his head and smooth. "Please, turn me back! I promise, I'll... Mmmph!! MMMfff!!!" His voice was cut off then muffled as Bob's mouth was sealed up and smoothed over then his eyes follows and can't see but can hear and feel unlike Jeff who can still see. Finally the last of Bob's skin color was soon replaced with black and then turned to spandex as the changes were almost complete.
Bob then feels his arms collapse and the binds that held them fell to the floor and his boxers fell as his crotch and waist soon collapse then his legs, arms, and then his head collapses and what replaced Bob's place is a living zentai/morphsuit as he muffle yells and wriggles to be changed back. Jake then walked up to zentaified Bob, "Well, you asked for it, now you'll end up in Jeff's closet until I decide what to do with Jeff. Bob whimpers and quivers in a mix of arousal and horror that he is a suit like Jeff that he fucked with. Jake folded the wriggling black zentai and placed him in Jeff's closet.
Jake then walked up to Jeff's crotch soiled suit form and picked him up. Jeff moaned wanting to be worn again. Jake sighs,"Well, I gotta wash you up ever since that bastard fucked you." Jake then turns on the shower and fills the tub with warm water and washes him. After washing and drying him up, Jake sets him on a hanger and left hanging to air dry on Jake's door while he thinks what to do as he sets up an alternate reality only that his parents and himself knows what happened to Jeff but everyone else knows that Bob and Jeff were always a living zentai suit. "Hmm..... What do I need to do next? No way in hell we're going to sell you though. Mom would kill me or dad if we did."