Apparently Mikuni Mizuki couldn't complete a chapter of this series focussed on Teana, so s/he released this instead (possibly with the yuri throwaway panel to entice the yuri fans) to tide the fans over.
You can easily tell this was done on short notice from the length and the fact that the third page's lower left panel is very similar to the cover of ~Fate hen 4~.
@Nanya: Did you manage to buy a copy of the "Bangai hen" of this series too?