Herbs can be flexible, and that gives them great power and potency if you're wise in their use. There's a reason folks who did magical work in Europe were once called Cunningfolk....cunning and intelligent are two traits you must have if you want to be successful here. Otherwise, you're just going to wind up being a dumb patsy who can't get anything done. Nature spirits are from nature, and thus have no real concern regarding whether or not they're honest, helpful, or harmful. Sometimes interactions with humans are there solely for the sake of the game. Just something to consider.
Basil (Ocimum basilicum)
It is, however, a notoriously powerful herb for seduction and the protection of one's love life. Today is Valentine's Day, so feel free to put it to good use. ;)
Benzoin (Styrax tonkinesis)
Black Henbane (Hyoscyamus niger)
It is the epitome of a twisting herb, however, and should only ever be used by someone who knows the spirit behind the plant intimately. If you haven't gotten both permission and schooling from Henbane's spirit, stay away. It can and will turn on you if given cause. Fair warning, it is slippery.
Bloodroot (Sanguinaria canadensis)
As a result, its also a mood-changing herb that can be used to modify the way someone feels about a situation. That can be plenty positive or rather negative depending on how you use it.....There is no evil in Earth that is not created or willed by Man.