Noah Centineo “loves” being “monogamous” with his girlfriend Alexis Ren

He said: “It’s the longest relationship I’ve ever been in. She’s very good at monogamy. Actually, I love monogamy too.”

Noah, 23, also spoke about having one night stands in the past, and revealed he doesn’t think they’re a “good” way to experience attraction.

He added: “Dude, you ever actually have one? 90 percent of the time, they’re not good.”

The ‘Fosters’ star previously battled drug addiction before becoming sober, and has described the period as a “really dark time” in his life.

Speaking to Harpers Bazaar’s men’s digital issue, he said: “There wasn’t really much I wouldn’t do. I never, ever injected anything, which is good. I smoked a lot of things. I was really upset, man. It was a really dark time in my life.”

Meanwhile, Noah previously spoke about the secret to his romance with Alexis, also 23, as he said the key to any relationship is “honesty”.

He said: "I think honesty is the biggest thing. Just be open about where you're at. If you're not into monogamy, talk to the person and be like, 'Hey, just so you know, I'm really digging this vibe, but I'm not trying to be boyfriend and girlfriend or be tied down. It's not where I'm at. If you're cool with that great. If you're not let's be friends.' Then no one gets hurt.

"Or if you're into monogamy just like date, see how it goes and then be like, 'Yo it's been real. We should totally take this to the next level.’ ”

The hunk's tips have worked in his own love life, as Alexis said her beau is the perfect boyfriend.

She gushed: "He's amazing. His heart is really that genuine. He has a heart of gold, and he's that much of a dork in real life, too."