It all began in 2010 when Courtney Dasher found a four-month-old Chiweenie with an exaggerated overbite, a lower jawline dysfunction, and a tendency to crawl on his belly because of the emotional trauma of being abandoned. She brought him home only intending to foster the pup, but that quickly changed. After a week, Dasher knew something was special about Tuna (a name based on his "cartoonish" features) and made the decision to adopt him.

Because of the impact he had on her life, Dasher felt that, perhaps, Tuna might be able to make a positive impact on other people too. When she started the Instagram account @tunameltsmyheart, she expected some people would call Tuna ugly. But Tuna has a beautiful soul, Dasher says, and her message of "loving the unlovable" has resonated with over a million followers.

With the launch of their new book, Tuna Melts My Heart: The Underdog with the Overbite, Dasher and Tuna are hitting the road and will be raising money for PAWS Chicago at an event cosponsored by the Book Cellar on Thursday.

"By partnering with shelters and donating a portion of proceeds throughout his tour, Tuna is helping to raise support and awareness for animal shelters across the country. Tuna is a wonderful example of the unconditional love, joy, and endless (toothy) smiles a rescue animal can bring," said PAWS community manager Sarah Ahlberg.

The event takes place at PAWS's Lincoln Park Adoption Center (1997 N. Clybourn), from 6-8 PM on Thursday, March 5. Tickets include a Q&A and book signing with Dasher, a copy of Tuna Melts My Heart: The Underdog with the Overbite, as well as a donation to PAWS.