Episode 13 of Kamisama no Inai Nichiyoubi, included in the final Blu-ray/DVD volume of the series.
This bonus episode is separated into three parts.
In the first part, taking place before the characters reach Ostia, Ai and the others visit a hot spring.
In the second part, Alice remembers the times he killed his classmates and encounters Hampnie Hambart. A battle ensues.
In the third and final part, Hampnie dreams of when he first met Hana and is then woken up by Ai.