- "Failure is nothing to be ashamed of. If you learned something from it, it's possible to gain that lost ground and then some. And all you have to do is avoid making that same mistake twice."
- — Crim —
Epitaph is the ninth episode of .hack//SIGN.
BT meets with Subaru, who seems to know more about the Key than Crim does. BT asks what she knows about the origin of the rumor of the Key. Subaru explains that the original BBS post about the Key was unreadable in some parts and originally written in German. The post was deleted quickly, adding to its mystery.
Tsukasa, having decided to care for the Grunty, brings food for it but soon realizes that it is gravely ill. The NPC in charge tells him that the Grunty has "Grunty Distemper" and requires a "Purple Cherry" to cure it. Tsukasa decides to search it out in a snowy field. The search for the field is more difficult on Tsukasa, who, unlike ordinary players, can feel the extreme cold temperature and the piercing wind of the field and is prone to physical fatigue. During the search, Tsukasa flashes back to a childhood memory in the real world. Her walking alongside her bicycle, meeting a group of children and being ridiculed on the size and type of bicycle she had, it was clearly a mismatch. This event is an example of the abuses she went through during her life. This made her the perfect selection for Morganna's manipulation, with no desire to want to return to the real world, and every reason to want to escape it.
Meanwhile, BT meets with Bear and Mimiru and tells them about the original post about the Key of the Twilight. They agree that Mimiru should contact Sora and see if he has any contacts that are of use. Sora tells her that information can be found through Helba, whom Bear recognizes as a skilled hacker. In exchange for contact with Helba, Sora had to be allowed to join the group.
Mimiru leaves the meeting and gates into Dun Loireag, where she sees Tsukasa running to a Grunty stable. Tsukasa brings the Purple Cherry to the sick Grunty, but is too late. The Grunty dies just as its owner arrives. The girl scolds Tsukasa but is immediately approached by Mimiru, and the two argue over what happened. Tsukasa blames himself for not coming back in time and leaves, and Mimiru follows. Mimiru attempts to console him and asks why he agreed to the girl's request in the first place. Tsukasa explains that he felt the warmth of the Grunty and decided that he wouldn't allow it to disappear, but despite his promise, he failed.
- The concept of a girl entrusting a sick Grunty to a main character is later reused in the Legend of the Twilight episode, The Phoenix Feather.
- When Tsukasa comes to feed the baby Grunty before he realizes it is sick, he is holding a deflated Twilight Onion in his hand.
- The subtitles incorrectly spell apoptosis as "apotosis."
- In this episode, Bear gives Mimiru three guesses as to what his occupation is. She uses up her first guess thinking that he is a detective.