A kaiken (懐剣/怀剑) is a 20–25 cm long, single edged Japanese knife usually without ornamental fittings housed in a plain but lacquered mount.

It is easy to carry, has extremely close range attack capabilities, and is highly concealed.

Kaiken comes from Japanese samurai culture. Girls born in samurai families would carry a short sword in their pockets for self-defense when they go out. She is determined to protect herself as a samurai woman.

This is a cosplay prop my niece asked me to design...

Scabbard and handle: any material you like, wood or black recommended
Blade: Silver PLA
(All parts are standing, so make sure the panel has enough adhesion)
Use a little glue at the connection between the blade and the handle, and insert the blade into the handle.