Sen to Man c14

# Okurigana

"*Okurigana* are *kana* suffixes following *kanji* stems in Japanese written words." -Wikipedia

# Pad the squares

Shima is referring to *kanji* practice: repetitive writing to improve muscle memory and character recognition.
She uses the graph paper pictured on page 4, but she cheats by writing the *okurigana* (e.g. る) in the rows instead of the adjacent columns where they belong. This way, she doesn't have to write as much.
They used horizontal-ruled paper in elementary school, however, so she couldn't waste as much space.