Online Application for Tourist Visa sponsored by boyfriend

Chaaaaarm

Good pm! I am trying to apply for tourist visa in Australia. My boyfriend's gonna finance all my expenses in the said trip, he's an Australian resident. I am a bit confused with the application form I am trying to fill up now. I am a medical student so I don't really have that much source of income, though I do have bank statement and my parents are financing me. There's a question in the application whether it's a self funded or supported by other, so I chose I supported by other as My boyfriend will be funding this trip. When I chose that, additional questions were added about the details of the person that will be funding me. It's asking what's the relationship between the applicant and the sponsor, but there's no boyfriend or friend as an option, closest is fiance, but I'm afraid they might require me another document for that which I don't have. Any suggestion of I should I do with this? Does anyone fill up the same form before and had the same issue?