Wilt Chamberlain may have spread his seed among many women, but Kobe spread his brain matter all over California.
Kobe's Brain Matter
Explanation
Explain Bear
Listen up, genius! This joke is saying Wilt Chamberlain got around with the ladies, but Kobe's brains were splattered all over California. Get it? It's dark because it's about death, and it's insulting to Kobe.