Explain in discrete steps how you imagine this works. What was the prevailing offer at the time you placed your order? How many coins did you buy before exhaust

Explain in discrete steps how you imagine this works. What was the prevailing offer at the time you placed your order? How many coins did you buy before exhausting displayed liquidity at 121.46? How do you imaging HTFs front-ran your purchase? how would things look differently in the absence of HFT?