Tantei wa Mou, Shindeiru - Episode 6 - Siesta Has Broken Foot

All that happened to Siesta after killing a monster and falling from Big Ben was a broken foot.

Siesta needed to stay in London while she healed, but why did Fuubi need to join her? Because Hel from SPES was still collecting hearts. Finding a little girl with amnesia appears unrelated, but that's never how these shows work.