What immediate effect does clerval's appearance in Ingolstadt have on Frankenstein?

Clerval's appearance in Ingolstadt brings a sense of relief and joy to Frankenstein, lifting his spirits and alleviating the heavy burden of guilt and sorrow he has been carrying since creating the monster. Clerval represents a connection to a more innocent, happier past, reminding Frankenstein of his former aspirations and friendships. This reunion temporarily distracts him from the consequences of his actions and reignites his passion for life and learning, although it ultimately foreshadows the impending tragedy that will arise from his scientific pursuits.