The reason Alyson Hannigan hated kissing Jason Segel on HIMYM

Alyson Hannigan adored her onscreen husband, Jason Segel, on How I Met Your Mother, but she absolutely loathed locking lips with him. The actress, who played Lily Aldrin on the series, confessed that kissing Segel, who starred as Marshall Eriksen, was almost an intolerable experience for her because of his smoker's breath.

"I cannot stand cigarette smoke. It's like kissing an ashtray and he's trying to be polite by having gum or mints, but it doesn't help," the Buffy The Vampire Slayer alum told Digital Spy. She tried to get Segel to curb the habit, she revealed, to no avail.

"When we started the pilot [for the show] he was like, 'Get me to stop smoking, I'll be your best friend.' So we did this bet where he would owe me $10 every time he had a cigarette. After the first day, he owed me $200," she recalled. "So he said, 'I'm just quitting,' and he quit cold turkey for about a year. It was fantastic but then ... he got stressed out and he started smoking again."

Despite his noxious nicotine habit, Hannigan adored working with Segel and was pretty heartbroken when How I Met Your Mother wrapped in 2014. The pair appeared together on The Talk in January 2014 and Hannigan wept on live TV over the end of the show.