Educate Yourself With Bruce And Roos: Word Balloon
From the artist~
Okay, so it turns out my biggest pet peeve with amateur comics is people not knowing what proper reading order for word balloons is. You can’t just put them wherever is most convenient for the rest of the picture, unfortunately.
Naturally, this applies to English, manga has its reading priority facing the top-right of the panel instead and tends to finish columns before continuing rows, on account of the native top-bottom, right-left writing direction. (Though they still group panels into rows instead of columns, mind.)