Definition of pipe for English Language Learners. : 1  a long, hollow tube for carrying water, steam, gas, etc. : 2  a tube with a small bowl at one end that is used for smoking tobacco. : 3  a musical instrument that is in the shape of a tube, has holes along the top, and is played by blowing.
The Blood of Olympus (mentioned) Lupa is the immortal Roman wolf goddess who trains Roman demigods in the ways of Rome. She trains the demigods at the Wolf House, then sends them to Camp Jupiter where they can join the Twelfth Legion.
The lessons wolf teaches are not always easy to swallow, but nevertheless necessary. Wolf is a symbol of guardianship, ritual, loyalty, and spirit. Wolf has the ability to make quick and firm emotional attachments, and often need to trust their own instincts. Thus they teach us to do the same, to trust our hearts and minds, and have control over our own lives.