Sumire is very much in the same line as Sky High or Souten, but unlike those two, which are all but identical, Sumire is noticeably different. It’s significantly more vivid, a very bright blue closest to Kon Peki or Diamine Mediterranean Blue, though it’s not an exact match for either. It’s absolutely gorgeous and quite easily readable but can be a bit bright to read whole pages of, if you’re sensitive to that. It does sheen with the classic pink/red sheen found in Souten and Sky High, but less so- more like the level of sheen in Kon Peki, which allows the base color to really show well. It’s a bit less syrupy-smooth than some Sailors, also. Still a very smooth, well-flowing ink, just not quite as cushiony. Again, more like a Pilot Iroshizuku line ink. A fantastic ink.