used the kanji version, dictionary spelling to get an accurate translation as possible from online translators (for the people who want to check it themselves)
あーでも先輩後輩かー
教室2個離れているだけで生きづらいのに
学年違ったら絶対いけないよね
Ah, senior and junior huh. . .
its hard being in different classrooms. . .
If you're in different grades, you definitely can't meet up.
not sure but i think she is just talking about the book(the summary/synopsis?)