Michael looks at Casey without giving any reaction, and then Casey starts to undress herself making her completely naked. Then she starts to take off Michael’s clothes and then she starts to kiss him. Michael can feel that his pussy is getting wetter and he feeling hornier and he can feels that his old friend on Casey’s groin is getting harder and bigger.

Casey starts to thrust in her new penis into Michael new vagina. Casey makes it hard and fast making Michael shout out for pain, but this not taking long and Michael starts to enjoy the sex with moaning out of pleasure. During the swap, Michael decided to takes Casey’s boobs and he focus on her boobs not letting her realise the change. He can feel the tightening occur on his chest and his chest become heavier but he can’t see anything. Suddenly he feels that Casey starts to fold and squish his new boobs and also licking his new bigger and more sensitive nipples making he feels the full experience of sex as a woman.

The sex takes up about half hour, then Casey cum inside Michael’s new vagina. After that Casey lays beside Michael panting of exhausted. Michael stands up after some rest then he notice that Casey’s bra is on the floor and he starts to think that what to do next. Then he decided to swap the knowledge of wearing bra, feeling of having breasts, memory of breasts and ownership of bra with Casey. Suddenly Michael feels that all the knowledge of wearing bra and the first time he wears a training bra and his breasts growing bigger until the current size which is C-cup breasts. Michael then smiles accepting the memory, after the flow end Michael takes up the bra and wear it without any problems. After done dress up, Michael now standing with his sister’s lower halves and having his girlfriend’s vagina and breasts. He feels that his t-shirt is too tight at the chest area because now he having breasts in front of his chest but he ignore it as he likes his current state plus he don’t want to having Casey’s clothes yet.

After that Michael leaves Casey and goes out from his room. As Michael goes to the living room, his sister, Michelle comes back home and also his mom coming back with full of groceries that she had bought just now. Michael decided to help his mom and Michelle follows too. With their help Laura finishes keeping the groceries fast and then she takes a break at the living room watching her favourite TV show.

At the same time, Michael and Michelle walk into Michelle’s room. Both of them start to discuss about the swap and Michael no need to tell Michelle what he had swapped with Casey because he lets Michelle to notice the swap. After sending Casey back home, Michelle tells Michael to complete swap with her torso. Michael always wants a girl’s torso after him having sex with Casey, so he accept Michelle’s request and starts the swap. He swaps all Michelle’s wardrobe for her upper body and her torso.

Michael feels the familiar tightening again, this time it flows through his torso. Michael looks at the full body length mirror in his sister’s room. He can see that his shoulder become smaller and lose all the muscle and body hair on it, the muscle change into feminine soft muscle that belongs to Michelle. Then his chest is changing into softer tactual and lost all the muscle and hair on it. All his body hair completely lost when his stomach start to changing form into Michelle’s nice and fit stomach. After his stomach changed his arms continue reform too without letting Michael to take some break of the swap. His arms become softer, smoother and slimmer into Michelle’s size. Then his hands change too into smaller size and his fingers become slightly longer and thinner.

After the all the physical change, Michael notices that his fingernails gained all the pink colour nail polish apply by Michelle just now on her fingernails and the nail polish is match to his toenails’. Then his clothes start to change at the same time he gained the nail polish. He can see that his t-shirt changing into Michelle’s by changing tactual and shape. Michael’s favourite polo t-shirt change into Michelle’s pink colour V-neck t-shirt in a minute time.

After the swap complete, Michael takes the advantage to swap all the memory of his current body and also the knowledge of taking care of the nails, to keep the body curve, fashion sense and also ways to take care of his new skin from Michelle. Then Michael lost his old body’s memory after the swap complete.

After everything is done Michelle looks at Michael and says, “…”

What did Michelle says? What the two brother-sister do next?
Please wait for the Part 5 to be release then you will know the answer. Thank you for reading and hope that I can get more suggestion from you all.