Bath time always is a intimate thing. Normally in a small cosy room, stripped down, clean, refreshed. Bathtubs are very near the top of the list of requests I receive. However they can be a little daunting. Bathrooms are typically quite small rooms. It makes shooting slightly more challenging, It also doesn't leave a lot of personal space to a client. which for some is the reason they eventually shy away from the idea. For clients that still like the idea about a boudoir session in a tub, get to know your photographer. Will you mind being stuck in a small room for a while with them. Trust is a big thing, and sometimes its takes some time to get. Ask them questions, get coffee, Then decide what you want to do.