This gives your partner a chance to object, and also to anticipate. Then I'm going to tickle you all over with feathers while you're helpless. Then you have to prepare ahead of time for whatever you've promised. Test ahead of time to see if the vibrator cord reaches the wall socket, the wrist cuffs and clips work, and the feathers are within reach. Once they get started, most couples find that exotic sex play is so exciting they automatically begin to think of new more exotic improvements for next time.
Mild pain is okay, as long as it's during intense sexual arousal when it's experienced as pleasure.
Since the excited state has ended, bondage could then be experienced as pain. Yet they must be able to instantly communicate if they're feeling real pain or actually need to stop for any reason. Discuss this with your partner, pick a word which is unlikely to come up in the planned fantasy, memorize it, and stop immediately if you hear it. One of the less-obvious dangers of exotic sex is that you get used to having a more exciting, different, fantasy type of sex and find regular romantic sex somehow lacking. To avoid becoming fixated or needing kinkier and kinkier sex, occasionally devote the same effort you'd invest in an exotic fantasy into an evening of old-fashioned romantic sex.