Understanding the poem 'Porphyria's Lover' by Robert Browning

The poem starts with the speaker feeling unsettled but is soon warmed physically and emotionally by Porphyria's arrival. Porphyria begins to undress and instigates intimacy with the speaker. The speaker seems to want ownership of Porphyria and is jealous she has a life outside of his. The speaker strangles Porphyria with her own hair and marvels how he can then keep Porphyria like a doll. Browning was writing at a time when Porphyria's sexual and suggestive manner would have been transgressive.