The punchline here is easy to miss, probably because of an awkward translation. In Uika's world, time started moving when Sakiko came back to her, hence the first year of the current era is 1 SCB. It's an allegory for how we track time with BC and AD. The joke is that Sakiko is Jesus Christ to her.

time power...

New
https://x.com/bangdream_en/status/1985663313233977586?t=Cy0OdhDoXl0rDKK6aeHdGA&s=19