In the beginning, there was no title. After the recording, Shoko said, I tried very hard to hold out, but the end of this piece suddenly fell (zukkoketa). Regardless, I was satisfied.
This composition combines images of the deep ocean and those evoked by C.W. Nichol's novel, Isana. Isana is the nickname that whalers used to call whales. The original arrangement was for 13 strings Koto (1991).