The god noticed nearby there was some mad scientists doing some tests on radiation on city animals and they had just irradiated a female chipmunk. The god nudged things a bit and the chipmunk escaped and managed to get herself outside to a nearby neighborhood. Ben walking from his bus-stop to his home saw the chipmunk which ran up to it. The world of Spectacle was weird and the chipmunk seemed to know him... or recognize him as a human. It's possible the chipmunk was family or some hero turned into a chipmunk.
Ben leaned down and asked "Hi little fella... Need so- OW!" The chipmunk bit him and Ben kicked the chipmunk who scampered down the street, and quickly got himself to his house where he went straight to his bathroom to disinfect and cover the bite. Darn thing drew blood and who knows what the thing had. Well the god knew, some weird DNA altering irradiated chipmunk saliva... If the god indeed had a face they were having a hard time keeping it straight.
At school some people noticed that Ben was gone from school the day Fred did some special magic mojo, and a few rumors were going on. Some people were talking about special medicine, or experimental surgery, or some special thing that Fred had been forcing on Ben to give him the best shot at getting Chad as his prom date. Fred himself just assumed that Ben may have just gotten sick or something, Prom was a long time away and anything could be happening. Said thing happening was a sick and mutating Ben was being taken from the general hospital to the Protector Building's hospital where he would be given adequate treatment and examination as they tried to figure out what was causing the mutations, and what exactly he was mutating into.
A few days later Ben had finished mutating and was given a decent enough examination. Ben mostly had 3 outcomes from the mutation. First he got cheek pouches. They didn't test them out much but Ben seemed to be able to carry stuff in them as if they were jacket or jean pockets. Second Ben was a bit more physically fit. Not amazingly physically fit just kinda slightly above average. Then the third outcome was that... Well Ben was now a girl, boobs and no balls, and the protectors had nothing to help with that last part. Doctor Doctor grabbed some DNA and proposed that Ben get a girl's name and try and transition. Ben had got a change of clothes and the following day entered school as Brenda. She wore a cap and had to draw on eyebrows as the irradiated mutations hadn't been kind to her hair... least that meant she didn't need to shave anywhere... Her mom had her wear a medium lengthen skirt and a black shirt/jacket... Along with a purse for everything she needed. People asking Brenda what happened were told "I was bitten by a wild radioactive chipmunk." By a Protector investigation the chipmunk was a runaway science experiment, and while his fortune hadn't come true yet... Brenda was a girl against all odds and Fred's outlandish fortune started seeming more likely. Heck Brenda had Chad's attention considering both the Fortune and the transformation. People were wondering if they could get Fred to give them a fortune... or maybe if they should get as far away from him as possible? Maybe call the Protector's on him?