This study investigates use and processing of emoji in chatbot conversations. 32 GenZ participants engaged in semi-naturalistic chats in an eye-tracker for ten minutes with a ChatGPT bot that used specific emoji from two personas (GenZ and Millennial). Eye-tracking and sentiment analysis revealed that the GenZ bot was typically positively perceived, while the Millennial bot showed one of two patterns: adaptation or hyperfocus on the ‘wrong’ emoji. The study sheds light on how emoji are used compared to words and their impact on AI assistant communication styles. The findings offer insights for studying open-ended conversations and linguistic patterns using ChatGPT.