Maruta
1) Maruta translates into the Japanese word for wood or logs.

2) The name of a Hentai comic

3) (commonly) Mad Scientist slang for one or more non volunteer human subjects.

Due to the mad scientists at Unit 731 and their use of the word as a secret synonym for "non volunteer human subjects"

the word will usually refer to "human subject", rather than actual "wood" when it is spoken in an non Japanese non wood related context.
Especially after the film "Men Behind the Sun" in which there is a scene explaining the meaning of "maruta" to a group of young cadets who have not done their homework.

The secret synonym of "logs" was chosen due to the fact that Unit 731 and its operations at a point was disguised as a lumber-mill, plus that most of the experiments would involve cutting up the logs and that these would be put in the stove and burned at the end to dispose of the evidence.

So if a mad scientists conducting some unofficial research asks you to bring maruta, he/she will usually be disappointed if you show up with firewood.

In popular culture:

As with many other Unit 731 related words it is also the name of a band and several songs in the heavy metal, thrash metal and Grindcore genre

4) It can be a Proper noun
"pick up that hitchhiker we are running low on maruta down at the labs"