Church

The church was Ragna the Bloodedge, Jin Kisaragi and Saya's childhood home.

Information
The church was founded and created by Celica A. Mercury. She took care of Ragna, Jin and Saya. However, an incident happened at the church involving Yūki Terumi. After Saya gave Yukianesa to Jin, the church was burned down and Celica was murdered. Ragna lost his arm and was left to die. Rachel Alucard, and later Jubei, found him there.

In Ragna's storyline in Continuum Shift, there is a flashback in which Jubei apologizes, supposedly to Celica, saying, "I got [Ragna] involved after all. I'm sorry. I really am. You can hate me if ya want. I promised I'd never use it again, but… I'm just gonna borrow this one more time…". Jubei is referring to the jacket and sword that Ragna uses, which were retrieved from the church by Jubei and given to Ragna. They were most likely kept by Celica following Bloodedge's death.

There are numerous points in the storyline, in both Calamity Trigger and Continuum Shift, in which characters come back to look at the remains of the church. Jubei, Rachel, and even Kokonoe herself have visited the site.