I have an idea why doesn't he become the step-dad of every protagonist of the world's he goes to(ex: kushina for naruto and mikoto for sasuke, ah yin for tang san)
This is just my opinion but "one piece world" would before "bleach world"
Bleach is very "messy" on the power scale of things so you should probably take your time before diving in so you have more prep before handling it
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