No premiere date announced yet. The source is from the official twitter account. Synopsis of the first season from AniList:
Amane lives alone in an apartment, and the most beautiful girl in school, Mahiru, lives just next door. They’ve almost never spoken—until the day he sees her in distress on a rainy day and lends her his umbrella. To return the favor, she offers him help around the house, and a relationship slowly begins to blossom as the distance between them closes…
Dangers in my heart is so good! Insomniacs After School season 1 is pretty slice of life-y, the start of the romance happens towards the end. Season 2 is definitely going to be more about the relationship between them