Koyoi Anata to Kiseki no Utage

From Chibi Manga:
The company vacation is the Magical Mystery Tour! She wants to confess to her former senpai, Izumi, at work whom she always admired. A President with poor management who has a desire to commit suicide, wants to part with her immortal partner. That partner is the knife bearer, Ritsuko. Haiyama who knows a lot about urban legends, the Takaku Temple…While waiting for the vacation, there is also a well established inn…Izumi kun’s Proprietress Madonna, Maki-san, specializes in history of justice. A knowledgeable clerk, Zenjiro, mysterious long term visitors, and an incognito investigator. And the start of the night banquet, of course something is bound to happen!!!