Warning! Spoilers for PPPPPP chapter 4 ahead!
Some of the best manga feature intense sibling rivalries, and Shonen Jump's newest series PPPPPP might just have the most intense of them all. The latest chapter introduces such a dynamic between protagonist Lucky and his brother Reijiro, and mangaka Mapollo 3 is hinting that readers might have to contend with six of these types of relationships.
Lucky's situation is especially unique for a number of reasons. First, he's a septuplet, so there are six potential rivalries. Second, the septuplets share the same passion - playing the piano - which increases the chance of them clashing. Third, their father is a world-renowned pianist who's frightfully competitive to a fault, so there is added pressure to rise to the top. Fourth, Lucky is estranged from all of his siblings because his parents divorced over his failure as a pianist. Fifth, Lucky still wants to become a pianist even though he has no talent.
Up until chapter 4 mangaka Mapollo 3 implied that Lucky most likely shared the same relationship with his siblings as his father, aunt and cousin. Lucky's father physically abused him for being talentless, and his aunt and cousin continued to mistreat him when he moved in with them. So PPPPPP readers understandably believed that Lucky's siblings would follow a similar pattern. Their rivalry, therefore, was expected to be something like Dragon Ball's Goku and Raditz who shared no feelings for each other. But that's not the case here at all.
In chapter 4 of PPPPPP, readers learn that Lucky and his brother Reijiro were quite close as children. Reijiro seemed to depend greatly on Lucky and wanted to do everything with him, partly because he didn't want to be alone. Lucky obliged because of his kindhearted nature. Reijiro also couldn't sleep alone and often pleaded Lucky to sleep with him, and Lucky always did. When they stumble across each other as adults, Lucky notices that Reijiro has massive bags under his eyes. This implies that he still struggles sleeping alone and either no one else is willing to sleep with him or Reijiro doesn't trust anyone else enough like he did Lucky. It's disheartening that when Reijiro and Lucky meet, Reijiro is first very kind towards his brother. But when he learns that Lucky is still pursuing the piano, he suddenly transforms, adopting the same cruel personality as his father, cousin and aunt. Reijiro tells his brother that someone as talentless as him should not pursue piano and just give up. Later on in chapter 5 when the two learn they will be competing in a future event, Reijiro revels in the fact that he will be able to knock Lucky down.
Although inherently different, the dynamic between Lucky and Reijiro is complicated in a similar way as the famous relationship between Sasuke and Itachi Uchiha from Naruto. The latter two originally shared a wonderful childhood until Sasuke eventually came to hate his old brother, dedicating his life to killing him. But Itachi still loved Sasuke. He only made himself out to be a dastardly villain to instill these feelings in Sasuke to atone for his own sins. In other words, the hatred was only one-sided. The same can be said of Lucky and Reijiro's current relationship. Lucky obviously still cares for and worries about his brother while Reijiro's mind has been infected by his father's warped ideals, causing him to possess negative feelings towards Lucky.
PPPPPP promises to surpass the tragedy of Sasuke and Itachi's relationship through the sheer number of siblings Lucky will have to compete against. It can be assumed that Lucky shares similar connections with his six other siblings, each of whom likely possesses their own nuanced dynamics than just plain hate. Even though it's highly unlikely their duels will be fatal like in Sasuke and Itachi's case, Shonen Jump's latest manga will assuredly bring readers to tears, at least six times.