Jiraiya went to where the shower was and began setting things up, the first thing he did was ensure that the door will be unlocked and that she'll have a GOOD view of his body, which he's rather proud of, to do that he defogged the glass and made it see through clear and ensured the curtains weren't closed, this is all to ensure when she comes in to 'prank' him all she'll see is him nude, more specifically his huge dick he's packing. Undressing and checking it out he grinned, putting that in her mind is merely a small step though, she'll try to ignore it, phase it out but all she needs to do is see it, after only seeing Minato's penis, she'll have something to compare to even on a subconscious level. Once that occurs he can begin the next step, for now though he stepped into the shower and began to 'clean' himself. He heard the quiet footsteps meaning Kushina was on her way, he had to ensure he didn't 'notice' her.
Kushina went up the stairs and heard the shower running, her plan is simple, sneak in and flush the toilet, that will cause him to get hit with cold water making him yelp, maybe that will cool his hormones. Kushina snickered to herself as she went to open the door of the bathroom, only to find it already open and Jiraiya showering with his erect penis in display, she gasped and blushed heavily as she stormed off. Jiraiya smirked as he heard her walk away, so far so good. Once he 'finished' his shower he got dressed and went downstairs he noticed Kushina trying to get the image out of her mind like he knew she would but it won't be that easy.
I've never seen a penis that big, I can't help but think about it. Jiraiya snickered as he implanted that in her mind, soon he saw her blushing as she thought about it more, her thoughts turning a bit dirty as she shook it off.
No, I have Minato! Kushina thought, was she turning into a pervert now, she hoped not. He saw her flushed look, and knew his plan was coming along nicely, and if everything goes well, she'll be jumping on him in no time.