We can see this glyph in Eb2-2 too. Otherwise it does not appear in Keiti. However, there are similar glyphs, e.g. Eb8-32:

Here we can recognize, to the left, the same kind of 'flow' that in Mamari perhaps indicates light emanating from the sun.

For some time now I have considered the curiously wide-spread legs as a way to describe the common Polynesian sitting posture. Sideways it would perhaps look like in e.g.

and with a front view it could have been carved as in the glyph we study here.

But there might be more involved. The feet in Eb8-32 seem to have been changed into fins or something similar and in Eb1-37 / Eb2-2 we cannot see the toes. Could it be that the front view with widely spread undulating legs indicates water? This would then perhaps not be a bathing person but a dead person, a person in the watery underworld.

With these ideas in mind it becomes clear why the hands have been changed into Y-shapes. I think that means that they are like branches, i.e. bony. No toes and no fingers. But the eyes are there anyhow, this spirit is still watching us.

There were no toes in the watery Wednesday as written in Large St Petersburg.

My explanation for the Y-shape as an open crotch is not invalidated by the idea of bones. Remember the skull of One Hunaphu in the fork of the calabash tree!