The latest episode of Bleach TYBW saw Kisuke Urahara contacting Gotei 13 Squad 12 Captain Mayuri Kurotsuchi. Despite the fact that Urahara is the person who helped Kurotsuchi reach his position, fans can often see the Squad 12 captain visibly detest the former head of Shinigami Research Institute.
The previous episode of Bleach TYBW saw Kisuke Urahara contacting Mayuri Kurotsuchi to help him relay a message to all Gotei 13 Captains and Lieutenants.
However, despite the fact that Urahara wanted to help the Shinigami reclaim their Bankai, Mayuri refused to help Urahara out of his distaste for him. While things worked out in the end, it left fans to wonder why Mayuri Kurotsuchi hates Kisuke Urahara.
Bleach TYBW: Mayuri Kurotsuchi wants to surpass Kisuke Urahara
While not much is known about Mayuri Kurotsuchi's past, the manga did show how Kisuke Urahara was the person who recruited him to be part of the Gotei 13 Squad 12 and the Shinigami Research and Development Institute. Mayuri Kurotsuchi was considered to be a very dangerous inmate, and was thus, confined within the Maggot's Nest.
However, one-day Kisuke Urahara visited Mayuri and offered him the chance to join him and become the Vice-President of Shinigami Research and Development Institute. Initially, Kurotsuchi declined the offer. However, after discovering that he would gain control over the entire institute in the event of Urahara's absence, he managed to persuade Mayuri to join.
As promised by Urahara, when he was exiled from the Soul Society, Mayuri Kurotsuchi took over as the Squad 12 Captain and the President of the Shinigami Research and Development Institute. Thus, many fans felt that Mayuri should have been grateful to Urahara for the opportunity. However, their relationship was much different than that.
While both scientists were brilliant in their work, there was a major difference between the two. While Kisuke Urahara was focused on his research and did not compare himself with someone else, for Mayuri Kurotsuchi the situation was quite different.
After he got out of the Maggot's Nest, he was looking for an opportunity to take over Urahara's position. Thus, for Mayuri, Urahara's position became the summit he needed to reach.
However, the issue did not get resolved even after Urahara got exiled. While Mayuri did reach the summit he was trying to reach, he did not ever become as relevant as Urahara.
Despite the fact that Urahara hadn't been to the Soul Society for 100 years, the Shinigami was still considered a genius and remembered by everyone. Every major event involved him, allowing him to be a center of attraction on many fronts, including the events surrounding Sosuke Aizen and Ichigo Kurosaki.
This must have led to Mayuri Kurotsuchi developing an inferiority complex toward Kisuke Urahara. Since then, the Squad 12 Captain has wanted to surpass the former President of Shinigami Research and Development Institute. This is probably why the current Squad 12 Captain shows a visible distaste for his former senior in Bleach TYBW.