Chatbots already exist, and have done so for decades. But the classical bots from "ye olden days" have their limits. They rely on a database of thousands of pre-made answers to pre-thought up conversation scenarios. Every time a user writes something, the bot looks through its database for an answer. If a user's question alternate a little from the bot's script, it's followed up by a standard "I don’t understand the question" reply. It's a stone sure way to find out if that sweet girl you're talking to on Tinder is actually a human..
I've saved the most difficult post for last in this run of summer-holiday-posts. The user. There are so many ways to represent a user, so the way you draw him/her depends on your context, on what you want to achieve. Note: All the "meanings" or "moods" written under the figures are my own. You can perceive them in a different way. The perceived meaning of symbols are heavily influenced by environment and culture.