An obsessed house mate has been jailed for at least 20 years for killing a "caring" primary school teacher in a horrific hammer attack.

Romanian Lucian Stinci, 34, was infatuated with Florina Pastina, 36, with whom he lived in a shared house in Alpha Road, Croydon.

Even though she showed no interest in him, he sent her Valentine's Day cards, describing her as the "most beautiful creature from the universe", the Old Bailey heard.

The night before the killing, he spent six hours drinking cider, taking six grams of cocaine and a Viagra-like drug as he watched sadomasochistic videos of women being tortured, raped, restrained and killed.

On the morning of July 19 last year, stilled "fired up" by the drugs and extreme porn, Stinci texted a colleague to say he had something to do before work.

Armed with a hammer from his bedroom, he hit Ms Pastina from behind as she made coffee in the kitchen.

He then continued to batter her over the head as she lay on the floor, causing blood to spatter over the walls and ceiling.

Stinci used the same hammer to batter her nephew and niece Nicholas Hellen and Claudia Pastina, both 25.

They fled the house and Stinci hid the weapon by the garden shed and changed his clothes before police arrived.

Last Friday, Stinci pleaded guilty to her murder as well as assault occasioning actual bodily harm, unlawful wounding and possession of cocaine.

Jailing him for life with a minimum of 20 years, Judge Marks said it was a "vicious" assault, fuelled by cocaine and "disgusting" porn material.

It was clear Ms Pastina's former pupils "thought the world of her" and she was an "understanding person who was greatly loved", he added.