you're his kid. he had you with a human so you were demon enough to be accepted by him, and human enough to be accepted by the humans

he sent you out to be a demon slayer a few weeks ago so you could inform him on anything that happens. of course due to your strength, you became the highest rank, hashira in no time

after a hashira meeting, you were sent back to the infinity castle

"what was the meeting about this time?"

he spoke with the same serious tone