It's a delicate power play between Pipotchi and Spike.
Between Pipotchi and Jimmy, they've worn the grooves of habit and behavior so deep that they could go through their routines blindfolded or have entire arguments play out without speaking. Pipotchi is a spoiled brat, but he will never do anything that would upset Jimmy, and thus a delicate balance is maintained.
With the ever ethical Spike, gets much more complicated because he will absolutely put his foot down and say "No." no matter how sweetly Pipotchi asks. While he finds this frustrating, it also makes Spike an intriguing puzzle for Pipotchi's devious mind, and the two of them remain diametrically opposed at opposite ends of the ethical spectrum.
As the eldest, Spike usually gets his way and Pipotchi will yield to him with varying degrees of reluctance.
While Pipotchi searches for new buttons to push and levers to pull in order to try and coerce Spike, Spike responds by proving himself almost incorruptible.
In the rare times Pipotchi coaxes him into lowering his guard, Spike must still stay vigilant, because Pipotchi is always watching him closely for his reaction, and one specific sign of weakness.

In the small bath Spike is forced to endure the gentle scrubbing of his soft fur. He is unsure if he's better off with this or in Specter's captivity, especially when Pipotchi has been waiting for opportunities like this one for years. Despite himself, Spike is enjoying the warm water, the special shampoo for his fur, the very careful way he's being scrubbed with the sponges.
He sighs, and then claps a hand over his mouth, looking fearfully at Pipotchi.
He heard it.
When Spike sighed, that meant Pipotchi had won.
The monkey Spike sank deeper into the bath, wishing it was deep enough to drown him.
Any attempt to reassert his authority would fail now, and Pipotchi knew it.
He didn't bother to close his eyes as a tiny watering can poured clean water over his head.
He thought this couldn't get much worse, because he didn't know about the studio Pipotchi had rented for his photo shoot.

Just realized when you mentioned him wishing to drown in the tub that getting body swapped probably lost EVERYBODY and competence in deep water. The Ape'd characters would now suddenly be very dense and heavy with the extra muscle while the Humanized characters now have completely new proportions if they could even swim to begin with. Blue and Red, as expected, would probably be the only cast members on the Apes side that can swim out of the box as humans due to Red picking up anything he needs too and Blue already taking to water like a fish, meanwhile Jimmy and Jake might be the only potentially good swimmers on the human side as they are used to having more muscle mass than the leaner characters.

Spike and Specter would both be completely fucked because Spike lost a LOT more height than the Chimp based swaps making him into a dense little monkey who has a lot less leeway before water goes over his head, meanwhile even if Specter learned how to swim by this point dropping the lanky 6' tall albino into the water in a new body would just activate his ape-brain and he'd panic instantly.

Oh no, that means Pipotchi and Jimmy will insist on Spike wearing those absurd baby life jackets.
Monkey!Spike just has a perpetual 😑 as his arms are held in a perpetual T-pose by the oversized life jacket vest.
"There! He's safe now!"
"What about Specter?"
"He'll be fine."
"He's splashing a lot and he looks scared."
"He's just playing."
"He's under the water and hasn't come up..."
"Look at Spike, he's so tiny!"
"Oh my gosh, he is!"