残 means to remain and is a JLPT N3 kanji. It has 10 strokes and uses the bone / death radical (歹).
Stroke order · 10 strokes
On'yomi (音読み)
ザン、サン
Kun'yomi (訓読み)
のこ(る)、そこな(う)
Radical
歹 · bone / death
Strokes
10
How to remember 残
What's left after cutting all the way to the bone (歹) — the remainder. 残業 (overtime) — the 'leftover' work at a Japanese office that never seems to end.