A huge number of posts about good questions to ask your girlfriend
For example, if you went to the park and she kept looking and touching the flowers, you can call her bumble bee. Another good source of inspiration and the most commonly used ones is food. You can choose from fruits, like strawberry or you can choose from sweets, such as cupcake. She will surely appreciate it that you think of her as something as cute and sweet as the fruits and sweets you use. Do not call her anything associated with heavy meals, like pork chop.