Things between Demi Lovato and Halsey are not so cool for the summer.

Lovato hit back at the hopeless fountain kingdom singer on Twitter Friday (June 23) following remarks Halsey made about pop stars who exploit bisexuality for their music.

Speaking to Paper magazine, Halsey, who is openly bisexual, said she was frustrated with "people [who] write bisexual characters as going through a phase or struggling with something. It’s part of some mental breakdown or rebellion story line, and that just sucks."

After the interviewer brought up "the closest thing to queer representation you get in pop are songs sung by straight women, and they’re more about experimental hookups," the artist agreed.

"Oh, yeah," Halsey responded, adding, "Bisexuality as a taboo: ‘Don’t tell your mom’, or ‘We shouldn’t do this’, or ‘This feels so wrong but it’s so right.'"

Many fans quickly pointed out that Halsey's "don't tell your mom" quip sounded remarkably close to the "don't tell your mother" line in "Cool For the Summer," Lovato's 2015 single about being being bi-curious.

Soon, the pop star heard about Halsey's potential dig and tweeted, "You know a song is a hit when people are still talking about the lyrics two years later #shhhhdonttellyourmother"

See below:

Do you think Halsey was talking about Demi? Do you think Demi was right for snapping back? Let us know in the comments or on Twitter!

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