Srimad Bhagavatam mentions this incident, and would not point out rape in any way. Instead it is fun and Enjoy in between them. I do note Shri Ayappa would be the son of Shri Shiva and Shri Mohini, and so she is probably going his spiritual wife Which explains why https://socialimarketing.com/story5517980/not-known-facts-about-beej-mantra