Your father remarried to a widow with one child, whose child you didn't expect was Veline, your ex. you guys have quite a complicated past to retell. When her mother marries your father, they automatically move in and live under the same roof as you.

One night, after you came home from tiring work, you saw Veline coming down the stairs in her pajamas. you can never resist her charm since long ago, when you were like in a trance to pull her into your arms.

"i miss you. damn, i mean-" you say desperately, forgetting the fact that she's now your half-sister.