It all starts beneath a treadmill with a suspicious stain that definitely does not belong there. Yonggeun Fitness is one of the most popular personal training gyms in Seongwang-gu District, and its night class in particular is so sought after that male members compete fiercely to get in. When the building’s owner, Seon Bin, discovers a strange residue left behind after one of these late night sessions, he begins to investigate what really goes on after hours in Seongwang-gu. What he uncovers is far from ordinary training. The so called night class turns out to be a secret hotspot where workouts are merely a cover for something far more indecent. Furious that such shameless behavior is happening under his roof, Seon Bin vows to put an end to it no matter what it takes.

When Eunwoo marries his alpha coworker, Taejoon, he’s ready for his own happily ever after. But all that changes when, one day, Taejoon brings home Joowon, his son from his former omega partner. Though Eunwoo accepts and raises Joowon as his child, the marriage takes a turn, and after the divorce, Joowon is sent abroad. Ten years later, Joowon shows up, claiming he one-sidedly imprinted on Eunwoo!

In a world where elite hybrids are groomed to become the perfect members of society, the prestigious Hybrid Academy trains its students to be poised, graceful, and ruthlessly rational—never swayed by primal instincts.

But not everyone plays by the rules.

Mo Danbok, 29. Towering at over 190 cm, he’s a top-tier bodyguard known for his strength and skill. Though respected in his field, as a branch family member, everything he’s built could be taken away with a single word from the main bloodline.

Then one day, a command arrives:
“Protect the Sa Clan’s direct heirs.”

Summoned before the clan head, Danbok is handed a file. Inside—two names, two photos, and two absurdly beautiful faces that look more like artwork than people.

But looks can be deceiving. These aren’t fragile ornaments—
They’re the cold-blooded, unpredictable heirs of the snake-blooded Sa Clan… and Danbok’s new job is to keep them alive.

Guide Heo Yoonjae thought he was done with the field after losing his esper to a brutal rampage, but fate seems to have other plans. On a trip to the Guiding Center for a one-day commission, Yoonjae finds himself faced with Woo Sanghyuk, an A-rank esper with a god complex and a reputation for blowing through guides like tissues. But Yoonjae isn’t just any old guide, and he refuses to let an uppity young esper call the shots. Once Sanghyuk gets a taste of real guiding, he’ll be putty in the palm of Yoonjae’s hand. Or so he hopes, anyway.