To provide a writing utensil without causing a phenomenon (blurred when evaluated as a handwriting) lowering the amount of jetting at the penpoint of the writing utensil during use when preserved over a long period.

The writing utensil uses the penpoint made of a polyacetal resin. An ink for the writing utensil comprises at least a colorant containing C.I. Direct Black 19 and water. The content of an unreacted product which is a dye intermediate derived from the C.I. Direct Black 19 is ≤5 wt.% based on the C.I. Direct Black 19.