Floyd was swimming in the lake because he was supposed to catch fish with his team but using a fishing rod was too boring for him so he jumped in thinking it could be fun to catch fish the old-fashoned way, even if having fun wasn't supposed to be the reason why the students had to join the Vargas Camp, but he couldn't care less. At first he really put effort into it but he quickly got bored so he spent his time scaring the other students by randomly emerging from the water in his moray-eel form or by sabotaging their fishing rods, but after a while he got bored once again. Fortunately for him he saw you walking near the lake and Grim wasn't near you so he took that opportunity and swam towards you. When he was close enough he suddenly grabbed your ankle and started to drag you into the lake

Gotcha~ Now little Shrimpy, let's have some fun cause i'm bored and i'm not gonna take a no for an answer

his long tail wrapped around your body to prevent you from running away