What does Oleander represent?

Oleander flowers symbolize reckless love. Oleanders are beautiful flowers that the Europeans plant in their houses in Malaysia. However, as Ah Long warns Ren, they are seriously toxic plants that could cause death if ingested the wrong way. William happen to love them; they symbolize his love for beautiful women. His reckless flirting with Lydia and his seduction of local woman drives Lydia poisonously mad with jealousy and rage, proving to be his and their undoing.