Check this out: furigana across a constituent boundary.

The target of the furigana here is the text コミックな一息, which would usually be pronounced komikku na ikinuki. The furigana, however, specifies that the na ikinuki is to be pronounced reriifu, thus giving us komikku reriifu, "comic relief."

This is unusual because while furigana usually target a constituent, these furigana cross the constituent boundary: komikku na | ikinuki. It's sort of an orthographic parallel to a non-constituent book title like A Scanner Darkly — not forbidden or anything, but kind of weird.

Here's what I think happened. The author (Takayama Hiroshi 高山宏) wanted to use "comic relief" as a straight-up loan. On the other hand, he (or perhaps his editor) was afraid that not enough readers would understand if it were just written in katakana. The word komikku is fairly common, but reriifu less so, so he replaced only the latter with a native Japanese word, ikinuki. This necessitated adding the na to komikku, since komikku is a "na adjective."

So now he has komikku na ikinuki and he wants to indicate that it should be pronounced as if it were a loan of "comic relief." He can't just change the ikinuki, because that would give you komikku na reriifu, which is rather affected: a calque of a phrase using the exact words in the phrase, loaned individually. On the other hand, if he applies the furigana komikku reriifu to the whole phrase, it looks strange to have furigana on katakana (komikku) that are the same as the actual katakana (komikku). "Comic [pronounced 'comic']".

Changing komikku to a native Japanese word and saving komikku for the furigana would be one way out of this dilemma, but instead he has simply applied reriifu to the entirety of the phrase that isn't komikku.

I can't believe how much I wrote about this.

Edit: Full citation:

Takayama, Hiroshi 高山宏. "Yume no kikagaku" 夢の幾何学 ["Geometry of a Dream"]. Sōseki kenkyū 8 (1997): 60-67. Print.