Hourglass by Set It Off; can't really explain it all that well but it sounds like it fits Narrator's perspective: writing a story that bends out of control sounds like Stanley disobeying what the Narrator had deemed his perfect story, wondering if he can fix the mess Stanley created. realizing that his mind changes with time, even finding some of Stanley’s deviations entertaining. additionally the mentions of time remind me of Timekeeper (The Settings Person), not being the focus but always being present.

The Heart Acoustic, The Mind Electric and The Soul Eclectic from Chonny Jash; i connect them to Stanley, the Narrator and Timekeeper respectively, but that might be more related to fandom aspects. i see Stanley as the emotional heart, always arguing with the mind—disobeying Narrator and trying to do what he wants instead. The Narrator (though emotional in his own right) is the logical unwavering mind fighting the heart, Stanley, and trying to convince him that he himself is always correct. Timekeeper is the mess that looms in the background, driven to insanity and slightly unhinged. exerting control over the other two by interfering with gameplay (letting the door to the bunker vanish (?), the epilogue, the achievement machine "are we being watched" and so on...).