The 'Girls' creator claims the 'Work' hitmaker is her ''greatest passion'' in life and she has an almost religious devotion to the Bajan beauty.
She said: ''She is my greatest passion in life. The way I feel about Rihanna is like the way some people, straight-up, feel about Jesus.''
The 30-year-old actress - who suffers from endometriosis, a condition where small pieces of the womb lining are found outside the womb - admitted she and partner Jack Antonoff are hoping to start a family once she has enjoyed a long period of good health and their career commitments don't get in the way.
She told Stella magazine: ''We would love to have children. We just need to make sure we are doing it at a time where it's not like, 'Congratulations on your baby', and he's like, 'I'm going to Australia for seven months'.
''Pregnancy is a huge physical change, and I have had such a raw experience with my body in my 20s that nothing could make me happier than just having a year of dancing around in my new, healthy body.''
Though Lena and her 32-year-old musician partner are very happy together, she is pleased they don't feel any ''pressure'' to get married.
She said: ''It's not that I am against marriage in any way, but I do like the fact that we have placed zero pressure on ourselves about it.''
And the actress insisted she isn't worried about getting older - just not ''developing'' as a person.
She said: ''I have such youthful parents, who are still so engaged with the work that they make, so I never see ageing as scary.
''What stresses me out is not getting older; it's the idea of not developing, of being stuck.''
It's time for a riot grrrl revolution.
How are the world's biggest superstars changing?
Who inspired Royse?
Graham J tells all about his experience with the Jazz Journal.
An interview with Nick Wilson.
This overlong comedy is so episodic that watching it is exactly like sitting through five...