There's a definite moment where Phillip isn't just providing support, he's also providing direction when he bumps that brightness setting up as they walk, Gustavain trailing off for a moment on whatever they're talking about. Really, while the other setting is the more obvious thing, whatever that setting is, is definitely the one that's dangerous. And because Gustavain is who he is and Phillip is who he is, it's dangerous for more than just the two of them, really. The level of trust here cannot be overstated, or perhaps the level of not giving a shit, but he knows Gustavain too well for that. And yet, fraught as all of this probably ought to be, there's something about Gustavain that reads not just pleased or pleasured but delighted.

"Later... later..." he waves away the request as he works to get Phillip out of his pants, "Been wanting to do this since you first touched the damn button." He takes him hot and hungry, deep, straight from the start and after a moment shoves Phillip's hips back against the wall so he can set his own pace, finally able to give voice to the moans he's been holding back, now that he's properly muffled.

All things considered, how controlling Gustavain is about this is probably a surprise-- but then they both know if Phillip wants something different, he can have it.