SANTA ANA (CBS) — A Fullerton man has been found guilty of ejaculating into his female co-workers water bottle.

Michael Lallana, 32, was found guilty Thursday afternoon of assault and battery. Jurors also found true the allegation that he did it for sexual gratification.

Lallana admitted in a taped interview submitted to jurors that he ejaculated into an “attractive” co-worker’s water bottle because “her lips had touched it,” but told detectives he never thought she would drink it.

Lallana and the woman — identified only as Tiffany G. — began working together at Northwestern Mutual Financial Network in Newport Beach. They were both later transferred last year to the company’s office in Orange.

“It was the closest I could ever get to someone as good looking as that without tampering with my marriage or hurting anyone,” Lallana said in the interview with Orange Police Department detectives in explaining why he ejaculated into the woman’s water bottle twice last year.

When the detectives quizzed him on why he didn’t just throw the water bottle away when he was done, Lallana said he figured she would dump the water and was afraid of leaving anything out of place on her desk.

“Can I honestly say I wanted her to drink it? No,” Lallana said in the taped interview. “Why I left it there, I don’t know.”

Tiffany testified that she left her water bottle on her desk in the Newport Beach office on a Friday in January of last year. She said that when she returned the following Monday and drank from the bottle, she tasted what she believed to be semen.

“I had a hunch that’s what it was, but I wouldn’t dream in a million years that’s what it was,” she said.

After being transferred to the company’s office in Orange, the woman said she again tasted semen in her water last April 6. Up to that point, she had been more careful with her water, dumping it when she left, she said.

Tiffany testified she threw the water bottle away that January. But after the second time in April, she kept the fouled liquid and asked her fiancee put his semen in a water bottle to see if that’s what she had tasted at work.

“At the time, I had no idea how else to figure out what this was,” she testified.

Convinced it was semen in the water bottle she had at work, the witness said she approached Orange police but was told they could not do anything based on the suspicion of a crime.

She then went to human resources officials at her workplace. “They heard me out, but they didn’t know what to do,” she testified. The woman said she was told the company’s legal representatives would be consulted but decided on her own to seek out an independent laboratory to test the water.

When she found a lab and got the results back, she had a friend, whose husband is a former Orange police officer, call the department’s investigators and they picked up the case in June, she testified.

Tiffany and Lallana did not have much to do with each other than small talk or an occasional greeting because he did much of his work outside the office, according to testimony.

When pressed by detectives, Lallana said he found his co-worker attractive and that part of the allure was that “her lips had touched” the water bottle, according to the tape played for jurors.

Lallana also gave investigators a DNA sample, and Deputy District Attorney Brock Zimmon told jurors the evidence showed it was Lallana’s semen in the water bottle.

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