Talk:Yōsuke Yoneya/@comment-38723092-20200614213659/@comment-856627-20200618184838

It IS Kogetsu. Ashihara even gives the backstory to it on BBF:

Q154: Who made Kogetsu (Spear) and when did it happen? A: Yoneya made it with one of the Chief Engineers. Due to the idea that "because the trion cost to construct the handle of a Kogetsu is lower than the cost to construct the blade, if the blade is shortened and the handle lengthened then even people without a high trion ability can have a long reach", it became a spear shape. Source: Border Briefing File, Question 154