Mr. K, this surprise is from your elder brother!

"The black seal was naturally the one originally found at the motorcycle instance. It's a rare sub-seal separated from a spatial treasure, capable of forming a spatial channel with its main seal that lasts for thirty seconds. 

Initially, Alexander had casually pocketed it, intending to hand it over to Louis when they met.

However, instead of meeting Louis, he first encountered a subordinate of Mr. K. 

As for the bell, it's needless to say that it came from the soul bell of Hell's Warriors.

"Mother-child seals! Could you really be Mr. K's elder brother?"

Seeing Alexander conjure a spatial portal, Gay, the Ghost King, began to believe him a bit. After all, such a lie would be easily exposed. 

As a Ghost King, thirty seconds is more than enough for several round trips. 

Only the person holding the main seal can close the spatial portal. If Alexander were deceiving him, he could come back at any time.