Implicit In-Context Learning compresses demonstration examples into a single context vector and injects it into the model’s activation space, achieving few-shot-level performance at near zero-shot inference cost. However, existing approaches typically aggregate demonstrations from all classes into a shared, task-level context vector, capturing global task information but without explicitly preserving fine-grained, class-conditional semantic distinctions. In this work, we propose Class-Conditional Context Vectors (C3V), a simple yet effective extension to implicit in-context learning that explicitly models class-specific contextual information by constructing separate context vectors for each class, without relying on explicit prompts. These class-conditional context vectors are additively injected into the model’s residual streams in a single forward pass, enabling contextual contributions to be modulated in a class-aware manner while keeping the backbone frozen. We evaluate C3V on multiple text classification benchmarks across several families of large language models. Experimental results demonstrate that C3V consistently outperforms task-level context vector baselines, and achieves higher average accuracy than conventional few-shot learning on most models.