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friend; ally; supporter
taking sides (with); supporting; standing by; backing up
困ったときに身方になってくれた。
They took my side when I was in trouble.
彼はいつも弱い者の身方をする。
He always sides with the underdog.
身方が多いほど心強く感じる。
The more allies you have, the more reassured you feel.