Lover's Embrace

Lover's Embrace is a temporary perk that grants the player character a +15% experience boost for 12 hours, after sleeping any amount of time in an unowned bed with a companion, with whom the player has a romantic relationship in Fallout 4.

Lover's Embrace replaces the Well Rested perk. When sleeping, the Sole Survivor will obtain one or the other, but not both. If the player character already has the Lover's Embrace perk and attempts to sleep away from their companion, they still will not obtain the Well Rested perk.

Bugs

 * It is possible to receive two copies of the Lover's Embrace perk simultaneously, if two romantic companions are present; however, this appears unintentional and does not happen every time. After the 12 hour period where both should wear off, the perk can bug, leaving one on the player character permanently, but without any actual benefit, preventing any rested bonus going forward.
 * Sometimes both the Lover's Embrace and the Well Rested bonus are given, adding up to a total of +25% experience while they last. Once the 12 hours are over, both perks expire with no known side effects.