Every once in a while Koichi will move in an unimaginable way while he's working.
Can you imagine having a job where you visit temples and shrines to collect their red ink stamps in a book?
If you want to learn how to vomit without sticking your finger down your throat, just imagine Koichi naked.
To do a concept of an image (in your mind) would require you to imagine it, because it's just a concept and not real.
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.