Fred makes a angry remark to Bob about him ruining women, implying Bob's recent date with Alida had entailed sex. Bob refutes that insisting his intentions were honorable.
In an illustrative scene, Bob is characterized as a womanizer when he is seen leafing through his Black Book when he attempts to make a date with Alida. The book consists of many cut-out photos of women along with their names, showing him to have known many women. It's a detail that does not escape Alida as she alludes to the book later.