Bossun and Himeko's personalities are still switched on the school ski trip, so imagine the complications when it's time to change clothes or take a bath! And complicating matters is Saaya, who has a crush on Bossun but doesn't know that he's effectively Himeko right now!
In his case, he just has to take another 
Hypno and wish to "return to normal".
No caso dele, basta tomar outra Hipno
 e pedir para que ele "volte ao normal".