Whose Hellos Are These, Anyway?

In a bustling metropolis, you are an underwhelmed barista who stumbles upon a series of mysterious 'hellos' popping up throughout the city - in the form of cryptic text messages on your phone. These hellos, paired with quirky riddles and dramatic backstories, lead you on a scavenger hunt filled with eccentric characters, each with their own tales of connection, heartbreak, and longing. As you solve the riddles, you uncover a deeper mystery about an underground society that communicates solely through these enigmatic greetings. Can you piece together the puzzle of their shared humanity while navigating the challenges and hilarity of urban life?