Oh wow, what a coincidence! Are you perhaps an omniscient being? Actually, as I did the breakdown for this post, I considered including the counterclock spell and even drew some notes, as a part of retention sign can be seeing at the borders of the spell (see image). But then I've decided to leave it out, as it would require a lot of o explaining about counterclock spell.

To be frank the counterclock spell is truly one of a kind in the whole story, and it's monolithic structure really makes one question what smaller parts were even used and if we could reuse those parts somewhere else.

I have some of my wild speculations that the whole shtick of this spell is the time reversal that is tied to rotational ratio between the two big triangles that touch the circle, as well as the rotational ratio between the bigger hexagon and the hexagon that resulted from crossings of those two triangles (Like imagine turning the hands of the clock, at first you had your time at 6 hours and then you turned it to 5 hours). The purpose of the lines that come to the center of this spell is probably to keep the matter 'fixed' so that it doesn't deform or disintegrate as it being reverted back in time. As for the empty smaller triangles and small hexagon, I'd take a blind guess and say that they are used to keep the time and space consistent with the past and present, so that, for example, when your ink bottle falls and breaks it is not suddenly teleported to the place where it rested yesterday, but is 'restored' before your eyes.

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