What is bunbering?

Answer 1

'Bunbering' or to bunber.

It's the effect to cojole someone to believing your intentions are good.

To mislead through a continuous act of well-meaning behavior.

The end result being the mark will have enough trust and act in a way that is friendly toward an otherwise malevolent partner or group.

It's a trick. Act well meaning then pull a fast one.

Answer 2

There seems to be a typo in your question. If you meant "bumbering," it is not a commonly recognized term. Can you provide more context or clarification?