The 25-year-old said in a video shared on YouTube: "I am here to make a formal announcement today. I am planning on making a sex tape if I reach a million subscribers.
"If you want to see me get f***ed, subscribe to my channel."
And her filthy promo tactic has worked.
At the time Lena released her pledge, she has 32,000 followers - now, she has 381,000.
Meanwhile, Adam's channel has reached 419,000 subscribers.
Now, the vloggers, who are dating, filmed a video to explain their sex tape plans after Lena's promise went viral.
Adam said: "We had no idea that it was going to generate this much media interest.
"We are going to make a sex tape very soon."
He also joked that Lena's Instagram account may now get verified due to her notoriety.
"We are going to make a sex tape very soon."
He also joked that Lena's Instagram account may now get verified due to her notoriety.
See their video below.
Saying that the tape will be out by the summer at the rate subscriptions are rocketing, Adam said: "I'm sorry mom. You're gonna hate me. My mom is pretty good turning a blind eye to the stupid things I do."
Discussing the negative comments she has received for her pledge, Lena said: "I don't see it as sheer desperation because you and I are sexually really open.
"I find the comments about being a ho and a slut funny because… you're the only person I sleep with, so in my mind, that makes me not a ho."
She added that she believes it is sexist that her boyfriend isn't getting any backlash for filming the sex tape, while she is receiving abuse.
The stars added that they had been approached by Pornhub about their tape, and have not yet decided whether they will enlist a professional crew to film their sex session.
Discussing the negative comments she has received for her pledge, Lena said: "I don't see it as sheer desperation because you and I are sexually really open.
She added that she believes it is sexist that her boyfriend isn't getting any backlash for filming the sex tape, while she is receiving abuse.
The stars added that they had been approached by Pornhub about their tape, and have not yet decided whether they will enlist a professional crew to film their sex session.
Adam said: "Is it going to be a 45 minute porno movie or a ten minute sex tape? I don't know. I don't know what the people want."
YouTube guidelines prohibit the uploading of graphic sexual content, so it is unclear where Lena and Adam's tape will broadcast.
And Los Angeles porn star wanna be Lena, is known for posting provocative selfies in lingerie, with her YouTube bio boasting about her "big booty".
They previously filmed a vlog after having a threesome with Lena's roommate Emily.
