A jacket that does not close
Almost every jacket you own is built around a fastening. The buttons set the chest measurement, the chest measurement sets the size, and the size decides whether it works on you. A haori removes that whole chain. The front panels hang open, or meet and tie with a short cord, and nothing is ever pulled across the body. What follows from that is a garment with an unusually wide range of people it fits, and one that never argues with the clothes underneath it.
It is also why the shape reads as considered rather than casual. A jacket worn open because it does not fit looks like a mistake. A jacket designed to be worn open looks like a decision.
Cotton-linen denim instead of silk
A traditional haori is silk, and silk is the reason the originals drape the way they do. It is also the reason most of them live in a drawer. The Karo trades it for a cotton-linen denim, which changes the character in three useful ways: it holds a fold rather than sliding out of one, it takes a cold wash without ceremony, and the linen in the blend keeps it breathable once the temperature climbs.
The weight matters more than it would on a fitted jacket. An unstructured shoulder has nothing holding its line, so the cloth has to do it. Too light and the whole thing collapses; this one has enough body to hang.
The sleeve, the shoulder and the hem
Three details define how this sits. The shoulder seam is dropped well past the natural shoulder, which is why the measurement on the chart looks enormous and why it should not be compared with a Western jacket. The sleeve is three-quarter and wide through the bicep, which is traditional for the shape rather than a shortened sleeve, and it is what lets the jacket go over a long-sleeve tee without bunching at the forearm. The hem falls at or just below the hip, 72cm at the smallest size and 77cm at the largest.
Choosing a size, and wearing it
Read the chest number and ignore the letter. The chart gives the full chest circumference measured flat on the garment, from 111cm at S to 136cm at 3XL. For a jacket that sits relatively close, pick the size about 12cm above your own chest; for the deliberately oversized drape the shape was made for, go further up. Neither is wrong, and because nothing fastens, neither will pull.
Keep what is underneath plain, because the jacket is the shape in the outfit. A tee, a plain long sleeve, wide trousers. Low shoes rather than tall boots, so the hem has a clean line to end on. It layers over a hoodie without the bulk a bomber would add, and over a shirt it reads closer to tailoring than to outerwear.
