Pilot Iroshizuku Tsuki-yo (“moonlight”) is a lot like Pilot Iroshizuku Rikka, but much darker (except Tsuki-yo came first). Like Rikka, it’s practically blue on Iroful while it’s teal on Col-o-ring and MD. Though in all cases it’s much darker than Rikka. The sheen is even darker, it’s more of a maroon than a red or magenta.
Scans
On col-o-ring it’s a very dark teal, on MD it’s slightly lighter but still dark Teal, and on Iroful it’s a dark blue-green. Also like Rikka, the scans are a little more green than the photos.
Photos
The sheen is a very reflective dark maroon, but it mostly shows in the large swatches.
In the writing there are traces of sheen around the edges, but it’s subtle.
Microscope
The sheen primarily sticks to the edges of lines, but occasionally has higher coverage. The color difference between Iroful and the others is even more apparent here.
Chromatography

It starts blue, then a large area of cyan, then a wide band of red-orange and then a tiny yellow line past the leading edge.

There is a dull purple glow under the red-orange band, and then a blue halo past the leading edge again. However, the swatches had no reactions.
Verdict
I was gifted this ink during a Secret Santa exchange, so the overlap with Rikka isn’t really an issue for me. I like the color it presents as on Iroful paper.
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