Complex sentence: The series starts with Ren in school, getting high grades and wishing Himeka would notice him, this is all interrupted however when Konkon comes in, and jumps on Ren saying that she "has come to repay him".
Split into simpler sentences: The series starts with Ren in school, getting high grades, and wishing Himeka would notice him. However, this is all interrupted when Konkon comes in and jumps on Ren, saying that she "has come to repay him".