With a cheery, crooked-toothed grin, Abu Sin has been trying to steal the heart of a 21-year-old American YouTuber named Christina Crockett for months. And now the Saudi Arabian teen is in jail for it.

Abu Sin, whose nickname loosely translates to "toothless," has been video chatting with Crockett on YouNow, and their conversations are mostly giggling flirtations and teasing made more endearing by a constant language barrier.

On YouTube, the videos have have been viewed tens of thousands of times. Sin, 19, was arrested by Saudi police on Sunday, in the Saudi capital of Riyadh, for the videos that authorities later described as "unethical behavior," France 24 reported. He could face up to three years in prison.

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Moments before his arrest, Sin was using YouNow to chat with a man from Kuwait. In a video of their chat, beginning at 6 minutes and 52 seconds, a police car is seen driving up to Sin, and the Kuwaiti man begins imitating the sound of police sirens.

On Monday, Riyadh police said Sin was using the live-blogging service YouNow "abusively," according to Saudi newspaper Okaz. The police asked that people report similar situations in order to "preserve the values" of Saudi communities.

Many commentators on Sin's videos "demanded for him to be punished for his actions," Col. Fawaz Al-Mayman, a police spokesperson, told The Saudi Gazette.

“The two of them [Sin and Crockett] composed enticing videos which received thousands of followers and viewers from all over the world within a short period of time," Al-Mayman told the Gazette. "Most of the viewers were from the Arab world. Abu Sin...became famous and received negative attention."

Saudi lawyer Abdulrahman al-Lahem told Okazthat Sin could face one to three years in prison.