Junkyard dog

The junkyard dog is a character found during a random encounter in Fallout 4.

Background
The junkyard dog appears to be a Rottweiler which can be bought from Gene, her current master. She was bred by and raised by Gene, and is potentially for sale to someone who he deems acceptable. Gene is extremely loath to sell her but if the Sole Survivor can pass a Charisma check of six or higher he can be persuaded to, painfully, let her go for 250 caps.

Other interactions

 * If bought, the junkyard dog can be sent to any workshop settlement, and will count for five points of defense. She will also go into a doghouse to rest just like Dogmeat.
 * If she enters a settlement in workshop mode, she can be moved to the current or another settlement without paying for her, she will add 5 defence and occupy a doghouse. Passing the Charisma check with Gene may be necessary first.
 * When looking to find the junkyard dog at the settlement selected when purchased, she will be found at any available doghouse. One can remove all existing ones then place a new one where the player character prefers her to be located.
 * In the workshop interface the Sole Survivor can select/move the doghouse and she will follow around while carrying it.
 * Unlike with Dogmeat or settlers the Sole Survivor cannot trade with the junkyard dog. However, items can be equipped with console commands or by reverse pickpocketing her to equip dog armor.
 * It is possible to encounter Gene again after purchasing a first junkyard dog. If this occurs a Charisma check is not required to purchase another dog, nor is the conversation as long as the Sole Survivor states that they would like to purchase another dog.
 * The junkyard dog is the only NPC in the game with  which counts towards increasing settlement Happiness.
 * The junkyard dog's equipment may randomly change over time between the various items that Dogmeat can equip.

Appearances
Junkyard dog appears only in Fallout 4.

Bugs

 * If you purchase multiple junkyard dogs from Gene it can change their model I.e. Fur color change ( Bug fix : reload a previous save before purchasing if possible then reload present save ).