>Poisoning can be induced from as few as five raw beans, and symptoms occur within three hours, beginning with nausea, then vomiting, which can be severe and sustained (profuse), followed by diarrhea.
Another issue might be that the water used for soaking, will froth up, and start to smell bad. This happens if it is let standing for longer than 12 hours usually.
That's all you need. Thorough cooking deactivates the phytohaemagglutinin, which otherwise would give you a bad time https://en.wikipedia.org/wiki/Phytohaemagglutinin
>Poisoning can be induced from as few as five raw beans, and symptoms occur within three hours, beginning with nausea, then vomiting, which can be severe and sustained (profuse), followed by diarrhea.