Link is a YouTube clip, which contains spoilers from the finale of the Super S arc in Sailor Moon.
At the 4:49 mark in [SPOILER]
this video[END OF SPOILER], while Helios is talking with Endymion, he abruptly changes his choice of pronoun from "boku" to "watashi." Why is this? I'm aware, for example, why a person would discern between "ore" and "boku/watashi," but I wasn't aware there was any kind of honorific discrepancy between "boku" and "watashi." Isn't the difference only a matter of either masculinity or gender neutrality?